/* C++ Parser. Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc. Written by Mark Mitchell . This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see . */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "dyn-string.h" #include "varray.h" #include "cpplib.h" #include "tree.h" #include "cp-tree.h" #include "c-pragma.h" #include "decl.h" #include "flags.h" #include "diagnostic.h" #include "toplev.h" #include "output.h" #include "target.h" #include "cgraph.h" #include "c-common.h" /* The lexer. */ /* The cp_lexer_* routines mediate between the lexer proper (in libcpp and c-lex.c) and the C++ parser. */ /* A token's value and its associated deferred access checks and qualifying scope. */ struct tree_check GTY(()) { /* The value associated with the token. */ tree value; /* The checks that have been associated with value. */ VEC (deferred_access_check, gc)* checks; /* The token's qualifying scope (used when it is a CPP_NESTED_NAME_SPECIFIER). */ tree qualifying_scope; }; /* A C++ token. */ typedef struct cp_token GTY (()) { /* The kind of token. */ ENUM_BITFIELD (cpp_ttype) type : 8; /* If this token is a keyword, this value indicates which keyword. Otherwise, this value is RID_MAX. */ ENUM_BITFIELD (rid) keyword : 8; /* Token flags. */ unsigned char flags; /* Identifier for the pragma. */ ENUM_BITFIELD (pragma_kind) pragma_kind : 6; /* True if this token is from a system header. */ BOOL_BITFIELD in_system_header : 1; /* True if this token is from a context where it is implicitly extern "C" */ BOOL_BITFIELD implicit_extern_c : 1; /* True for a CPP_NAME token that is not a keyword (i.e., for which KEYWORD is RID_MAX) iff this name was looked up and found to be ambiguous. An error has already been reported. */ BOOL_BITFIELD ambiguous_p : 1; /* The value associated with this token, if any. */ union cp_token_value { /* Used for CPP_NESTED_NAME_SPECIFIER and CPP_TEMPLATE_ID. */ struct tree_check* GTY((tag ("1"))) tree_check_value; /* Use for all other tokens. */ tree GTY((tag ("0"))) value; } GTY((desc ("(%1.type == CPP_TEMPLATE_ID) || (%1.type == CPP_NESTED_NAME_SPECIFIER)"))) u; /* The location at which this token was found. */ location_t location; } cp_token; /* We use a stack of token pointer for saving token sets. */ typedef struct cp_token *cp_token_position; DEF_VEC_P (cp_token_position); DEF_VEC_ALLOC_P (cp_token_position,heap); static cp_token eof_token = { CPP_EOF, RID_MAX, 0, PRAGMA_NONE, 0, false, 0, { NULL }, 0 }; /* The cp_lexer structure represents the C++ lexer. It is responsible for managing the token stream from the preprocessor and supplying it to the parser. Tokens are never added to the cp_lexer after it is created. */ typedef struct cp_lexer GTY (()) { /* The memory allocated for the buffer. NULL if this lexer does not own the token buffer. */ cp_token * GTY ((length ("%h.buffer_length"))) buffer; /* If the lexer owns the buffer, this is the number of tokens in the buffer. */ size_t buffer_length; /* A pointer just past the last available token. The tokens in this lexer are [buffer, last_token). */ cp_token_position GTY ((skip)) last_token; /* The next available token. If NEXT_TOKEN is &eof_token, then there are no more available tokens. */ cp_token_position GTY ((skip)) next_token; /* A stack indicating positions at which cp_lexer_save_tokens was called. The top entry is the most recent position at which we began saving tokens. If the stack is non-empty, we are saving tokens. */ VEC(cp_token_position,heap) *GTY ((skip)) saved_tokens; /* The next lexer in a linked list of lexers. */ struct cp_lexer *next; /* True if we should output debugging information. */ bool debugging_p; /* True if we're in the context of parsing a pragma, and should not increment past the end-of-line marker. */ bool in_pragma; } cp_lexer; /* cp_token_cache is a range of tokens. There is no need to represent allocate heap memory for it, since tokens are never removed from the lexer's array. There is also no need for the GC to walk through a cp_token_cache, since everything in here is referenced through a lexer. */ typedef struct cp_token_cache GTY(()) { /* The beginning of the token range. */ cp_token * GTY((skip)) first; /* Points immediately after the last token in the range. */ cp_token * GTY ((skip)) last; } cp_token_cache; /* Prototypes. */ static cp_lexer *cp_lexer_new_main (void); static cp_lexer *cp_lexer_new_from_tokens (cp_token_cache *tokens); static void cp_lexer_destroy (cp_lexer *); static int cp_lexer_saving_tokens (const cp_lexer *); static cp_token_position cp_lexer_token_position (cp_lexer *, bool); static cp_token *cp_lexer_token_at (cp_lexer *, cp_token_position); static void cp_lexer_get_preprocessor_token (cp_lexer *, cp_token *); static inline cp_token *cp_lexer_peek_token (cp_lexer *); static cp_token *cp_lexer_peek_nth_token (cp_lexer *, size_t); static inline bool cp_lexer_next_token_is (cp_lexer *, enum cpp_ttype); static bool cp_lexer_next_token_is_not (cp_lexer *, enum cpp_ttype); static bool cp_lexer_next_token_is_keyword (cp_lexer *, enum rid); static cp_token *cp_lexer_consume_token (cp_lexer *); static void cp_lexer_purge_token (cp_lexer *); static void cp_lexer_purge_tokens_after (cp_lexer *, cp_token_position); static void cp_lexer_save_tokens (cp_lexer *); static void cp_lexer_commit_tokens (cp_lexer *); static void cp_lexer_rollback_tokens (cp_lexer *); #ifdef ENABLE_CHECKING static void cp_lexer_print_token (FILE *, cp_token *); static inline bool cp_lexer_debugging_p (cp_lexer *); static void cp_lexer_start_debugging (cp_lexer *) ATTRIBUTE_UNUSED; static void cp_lexer_stop_debugging (cp_lexer *) ATTRIBUTE_UNUSED; #else /* If we define cp_lexer_debug_stream to NULL it will provoke warnings about passing NULL to functions that require non-NULL arguments (fputs, fprintf). It will never be used, so all we need is a value of the right type that's guaranteed not to be NULL. */ #define cp_lexer_debug_stream stdout #define cp_lexer_print_token(str, tok) (void) 0 #define cp_lexer_debugging_p(lexer) 0 #endif /* ENABLE_CHECKING */ static cp_token_cache *cp_token_cache_new (cp_token *, cp_token *); static void cp_parser_initial_pragma (cp_token *); /* Manifest constants. */ #define CP_LEXER_BUFFER_SIZE ((256 * 1024) / sizeof (cp_token)) #define CP_SAVED_TOKEN_STACK 5 /* A token type for keywords, as opposed to ordinary identifiers. */ #define CPP_KEYWORD ((enum cpp_ttype) (N_TTYPES + 1)) /* A token type for template-ids. If a template-id is processed while parsing tentatively, it is replaced with a CPP_TEMPLATE_ID token; the value of the CPP_TEMPLATE_ID is whatever was returned by cp_parser_template_id. */ #define CPP_TEMPLATE_ID ((enum cpp_ttype) (CPP_KEYWORD + 1)) /* A token type for nested-name-specifiers. If a nested-name-specifier is processed while parsing tentatively, it is replaced with a CPP_NESTED_NAME_SPECIFIER token; the value of the CPP_NESTED_NAME_SPECIFIER is whatever was returned by cp_parser_nested_name_specifier_opt. */ #define CPP_NESTED_NAME_SPECIFIER ((enum cpp_ttype) (CPP_TEMPLATE_ID + 1)) /* A token type for tokens that are not tokens at all; these are used to represent slots in the array where there used to be a token that has now been deleted. */ #define CPP_PURGED ((enum cpp_ttype) (CPP_NESTED_NAME_SPECIFIER + 1)) /* The number of token types, including C++-specific ones. */ #define N_CP_TTYPES ((int) (CPP_PURGED + 1)) /* Variables. */ #ifdef ENABLE_CHECKING /* The stream to which debugging output should be written. */ static FILE *cp_lexer_debug_stream; #endif /* ENABLE_CHECKING */ /* Create a new main C++ lexer, the lexer that gets tokens from the preprocessor. */ static cp_lexer * cp_lexer_new_main (void) { cp_token first_token; cp_lexer *lexer; cp_token *pos; size_t alloc; size_t space; cp_token *buffer; /* It's possible that parsing the first pragma will load a PCH file, which is a GC collection point. So we have to do that before allocating any memory. */ cp_parser_initial_pragma (&first_token); c_common_no_more_pch (); /* Allocate the memory. */ lexer = GGC_CNEW (cp_lexer); #ifdef ENABLE_CHECKING /* Initially we are not debugging. */ lexer->debugging_p = false; #endif /* ENABLE_CHECKING */ lexer->saved_tokens = VEC_alloc (cp_token_position, heap, CP_SAVED_TOKEN_STACK); /* Create the buffer. */ alloc = CP_LEXER_BUFFER_SIZE; buffer = GGC_NEWVEC (cp_token, alloc); /* Put the first token in the buffer. */ space = alloc; pos = buffer; *pos = first_token; /* Get the remaining tokens from the preprocessor. */ while (pos->type != CPP_EOF) { pos++; if (!--space) { space = alloc; alloc *= 2; buffer = GGC_RESIZEVEC (cp_token, buffer, alloc); pos = buffer + space; } cp_lexer_get_preprocessor_token (lexer, pos); } lexer->buffer = buffer; lexer->buffer_length = alloc - space; lexer->last_token = pos; lexer->next_token = lexer->buffer_length ? buffer : &eof_token; /* Subsequent preprocessor diagnostics should use compiler diagnostic functions to get the compiler source location. */ cpp_get_options (parse_in)->client_diagnostic = true; cpp_get_callbacks (parse_in)->error = cp_cpp_error; gcc_assert (lexer->next_token->type != CPP_PURGED); return lexer; } /* Create a new lexer whose token stream is primed with the tokens in CACHE. When these tokens are exhausted, no new tokens will be read. */ static cp_lexer * cp_lexer_new_from_tokens (cp_token_cache *cache) { cp_token *first = cache->first; cp_token *last = cache->last; cp_lexer *lexer = GGC_CNEW (cp_lexer); /* We do not own the buffer. */ lexer->buffer = NULL; lexer->buffer_length = 0; lexer->next_token = first == last ? &eof_token : first; lexer->last_token = last; lexer->saved_tokens = VEC_alloc (cp_token_position, heap, CP_SAVED_TOKEN_STACK); #ifdef ENABLE_CHECKING /* Initially we are not debugging. */ lexer->debugging_p = false; #endif gcc_assert (lexer->next_token->type != CPP_PURGED); return lexer; } /* Frees all resources associated with LEXER. */ static void cp_lexer_destroy (cp_lexer *lexer) { if (lexer->buffer) ggc_free (lexer->buffer); VEC_free (cp_token_position, heap, lexer->saved_tokens); ggc_free (lexer); } /* Returns nonzero if debugging information should be output. */ #ifdef ENABLE_CHECKING static inline bool cp_lexer_debugging_p (cp_lexer *lexer) { return lexer->debugging_p; } #endif /* ENABLE_CHECKING */ static inline cp_token_position cp_lexer_token_position (cp_lexer *lexer, bool previous_p) { gcc_assert (!previous_p || lexer->next_token != &eof_token); return lexer->next_token - previous_p; } static inline cp_token * cp_lexer_token_at (cp_lexer *lexer ATTRIBUTE_UNUSED, cp_token_position pos) { return pos; } /* nonzero if we are presently saving tokens. */ static inline int cp_lexer_saving_tokens (const cp_lexer* lexer) { return VEC_length (cp_token_position, lexer->saved_tokens) != 0; } /* Store the next token from the preprocessor in *TOKEN. Return true if we reach EOF. If LEXER is NULL, assume we are handling an initial #pragma pch_preprocess, and thus want the lexer to return processed strings. */ static void cp_lexer_get_preprocessor_token (cp_lexer *lexer, cp_token *token) { static int is_extern_c = 0; /* Get a new token from the preprocessor. */ token->type = c_lex_with_flags (&token->u.value, &token->location, &token->flags, lexer == NULL ? 0 : C_LEX_RAW_STRINGS); token->keyword = RID_MAX; token->pragma_kind = PRAGMA_NONE; token->in_system_header = in_system_header; /* On some systems, some header files are surrounded by an implicit extern "C" block. Set a flag in the token if it comes from such a header. */ is_extern_c += pending_lang_change; pending_lang_change = 0; token->implicit_extern_c = is_extern_c > 0; /* Check to see if this token is a keyword. */ if (token->type == CPP_NAME) { if (C_IS_RESERVED_WORD (token->u.value)) { /* Mark this token as a keyword. */ token->type = CPP_KEYWORD; /* Record which keyword. */ token->keyword = C_RID_CODE (token->u.value); /* Update the value. Some keywords are mapped to particular entities, rather than simply having the value of the corresponding IDENTIFIER_NODE. For example, `__const' is mapped to `const'. */ token->u.value = ridpointers[token->keyword]; } else { if (warn_cxx0x_compat && C_RID_CODE (token->u.value) >= RID_FIRST_CXX0X && C_RID_CODE (token->u.value) <= RID_LAST_CXX0X) { /* Warn about the C++0x keyword (but still treat it as an identifier). */ warning (OPT_Wc__0x_compat, "identifier %<%s%> will become a keyword in C++0x", IDENTIFIER_POINTER (token->u.value)); /* Clear out the C_RID_CODE so we don't warn about this particular identifier-turned-keyword again. */ C_RID_CODE (token->u.value) = RID_MAX; } token->ambiguous_p = false; token->keyword = RID_MAX; } } /* Handle Objective-C++ keywords. */ else if (token->type == CPP_AT_NAME) { token->type = CPP_KEYWORD; switch (C_RID_CODE (token->u.value)) { /* Map 'class' to '@class', 'private' to '@private', etc. */ case RID_CLASS: token->keyword = RID_AT_CLASS; break; case RID_PRIVATE: token->keyword = RID_AT_PRIVATE; break; case RID_PROTECTED: token->keyword = RID_AT_PROTECTED; break; case RID_PUBLIC: token->keyword = RID_AT_PUBLIC; break; case RID_THROW: token->keyword = RID_AT_THROW; break; case RID_TRY: token->keyword = RID_AT_TRY; break; case RID_CATCH: token->keyword = RID_AT_CATCH; break; default: token->keyword = C_RID_CODE (token->u.value); } } else if (token->type == CPP_PRAGMA) { /* We smuggled the cpp_token->u.pragma value in an INTEGER_CST. */ token->pragma_kind = TREE_INT_CST_LOW (token->u.value); token->u.value = NULL_TREE; } } /* Update the globals input_location and in_system_header and the input file stack from TOKEN. */ static inline void cp_lexer_set_source_position_from_token (cp_token *token) { if (token->type != CPP_EOF) { input_location = token->location; in_system_header = token->in_system_header; } } /* Return a pointer to the next token in the token stream, but do not consume it. */ static inline cp_token * cp_lexer_peek_token (cp_lexer *lexer) { if (cp_lexer_debugging_p (lexer)) { fputs ("cp_lexer: peeking at token: ", cp_lexer_debug_stream); cp_lexer_print_token (cp_lexer_debug_stream, lexer->next_token); putc ('\n', cp_lexer_debug_stream); } return lexer->next_token; } /* Return true if the next token has the indicated TYPE. */ static inline bool cp_lexer_next_token_is (cp_lexer* lexer, enum cpp_ttype type) { return cp_lexer_peek_token (lexer)->type == type; } /* Return true if the next token does not have the indicated TYPE. */ static inline bool cp_lexer_next_token_is_not (cp_lexer* lexer, enum cpp_ttype type) { return !cp_lexer_next_token_is (lexer, type); } /* Return true if the next token is the indicated KEYWORD. */ static inline bool cp_lexer_next_token_is_keyword (cp_lexer* lexer, enum rid keyword) { return cp_lexer_peek_token (lexer)->keyword == keyword; } /* Return true if the next token is a keyword for a decl-specifier. */ static bool cp_lexer_next_token_is_decl_specifier_keyword (cp_lexer *lexer) { cp_token *token; token = cp_lexer_peek_token (lexer); switch (token->keyword) { /* auto specifier: storage-class-specifier in C++, simple-type-specifier in C++0x. */ case RID_AUTO: /* Storage classes. */ case RID_REGISTER: case RID_STATIC: case RID_EXTERN: case RID_MUTABLE: case RID_THREAD: /* Elaborated type specifiers. */ case RID_ENUM: case RID_CLASS: case RID_STRUCT: case RID_UNION: case RID_TYPENAME: /* Simple type specifiers. */ case RID_CHAR: case RID_WCHAR: case RID_BOOL: case RID_SHORT: case RID_INT: case RID_LONG: case RID_SIGNED: case RID_UNSIGNED: case RID_FLOAT: case RID_DOUBLE: case RID_VOID: /* GNU extensions. */ case RID_ATTRIBUTE: case RID_TYPEOF: /* C++0x extensions. */ case RID_DECLTYPE: return true; default: return false; } } /* Return a pointer to the Nth token in the token stream. If N is 1, then this is precisely equivalent to cp_lexer_peek_token (except that it is not inline). One would like to disallow that case, but there is one case (cp_parser_nth_token_starts_template_id) where the caller passes a variable for N and it might be 1. */ static cp_token * cp_lexer_peek_nth_token (cp_lexer* lexer, size_t n) { cp_token *token; /* N is 1-based, not zero-based. */ gcc_assert (n > 0); if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: peeking ahead %ld at token: ", (long)n); --n; token = lexer->next_token; gcc_assert (!n || token != &eof_token); while (n != 0) { ++token; if (token == lexer->last_token) { token = &eof_token; break; } if (token->type != CPP_PURGED) --n; } if (cp_lexer_debugging_p (lexer)) { cp_lexer_print_token (cp_lexer_debug_stream, token); putc ('\n', cp_lexer_debug_stream); } return token; } /* Return the next token, and advance the lexer's next_token pointer to point to the next non-purged token. */ static cp_token * cp_lexer_consume_token (cp_lexer* lexer) { cp_token *token = lexer->next_token; gcc_assert (token != &eof_token); gcc_assert (!lexer->in_pragma || token->type != CPP_PRAGMA_EOL); do { lexer->next_token++; if (lexer->next_token == lexer->last_token) { lexer->next_token = &eof_token; break; } } while (lexer->next_token->type == CPP_PURGED); cp_lexer_set_source_position_from_token (token); /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) { fputs ("cp_lexer: consuming token: ", cp_lexer_debug_stream); cp_lexer_print_token (cp_lexer_debug_stream, token); putc ('\n', cp_lexer_debug_stream); } return token; } /* Permanently remove the next token from the token stream, and advance the next_token pointer to refer to the next non-purged token. */ static void cp_lexer_purge_token (cp_lexer *lexer) { cp_token *tok = lexer->next_token; gcc_assert (tok != &eof_token); tok->type = CPP_PURGED; tok->location = UNKNOWN_LOCATION; tok->u.value = NULL_TREE; tok->keyword = RID_MAX; do { tok++; if (tok == lexer->last_token) { tok = &eof_token; break; } } while (tok->type == CPP_PURGED); lexer->next_token = tok; } /* Permanently remove all tokens after TOK, up to, but not including, the token that will be returned next by cp_lexer_peek_token. */ static void cp_lexer_purge_tokens_after (cp_lexer *lexer, cp_token *tok) { cp_token *peek = lexer->next_token; if (peek == &eof_token) peek = lexer->last_token; gcc_assert (tok < peek); for ( tok += 1; tok != peek; tok += 1) { tok->type = CPP_PURGED; tok->location = UNKNOWN_LOCATION; tok->u.value = NULL_TREE; tok->keyword = RID_MAX; } } /* Begin saving tokens. All tokens consumed after this point will be preserved. */ static void cp_lexer_save_tokens (cp_lexer* lexer) { /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: saving tokens\n"); VEC_safe_push (cp_token_position, heap, lexer->saved_tokens, lexer->next_token); } /* Commit to the portion of the token stream most recently saved. */ static void cp_lexer_commit_tokens (cp_lexer* lexer) { /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: committing tokens\n"); VEC_pop (cp_token_position, lexer->saved_tokens); } /* Return all tokens saved since the last call to cp_lexer_save_tokens to the token stream. Stop saving tokens. */ static void cp_lexer_rollback_tokens (cp_lexer* lexer) { /* Provide debugging output. */ if (cp_lexer_debugging_p (lexer)) fprintf (cp_lexer_debug_stream, "cp_lexer: restoring tokens\n"); lexer->next_token = VEC_pop (cp_token_position, lexer->saved_tokens); } /* Print a representation of the TOKEN on the STREAM. */ #ifdef ENABLE_CHECKING static void cp_lexer_print_token (FILE * stream, cp_token *token) { /* We don't use cpp_type2name here because the parser defines a few tokens of its own. */ static const char *const token_names[] = { /* cpplib-defined token types */ #define OP(e, s) #e, #define TK(e, s) #e, TTYPE_TABLE #undef OP #undef TK /* C++ parser token types - see "Manifest constants", above. */ "KEYWORD", "TEMPLATE_ID", "NESTED_NAME_SPECIFIER", "PURGED" }; /* If we have a name for the token, print it out. Otherwise, we simply give the numeric code. */ gcc_assert (token->type < ARRAY_SIZE(token_names)); fputs (token_names[token->type], stream); /* For some tokens, print the associated data. */ switch (token->type) { case CPP_KEYWORD: /* Some keywords have a value that is not an IDENTIFIER_NODE. For example, `struct' is mapped to an INTEGER_CST. */ if (TREE_CODE (token->u.value) != IDENTIFIER_NODE) break; /* else fall through */ case CPP_NAME: fputs (IDENTIFIER_POINTER (token->u.value), stream); break; case CPP_STRING: case CPP_WSTRING: fprintf (stream, " \"%s\"", TREE_STRING_POINTER (token->u.value)); break; default: break; } } /* Start emitting debugging information. */ static void cp_lexer_start_debugging (cp_lexer* lexer) { lexer->debugging_p = true; } /* Stop emitting debugging information. */ static void cp_lexer_stop_debugging (cp_lexer* lexer) { lexer->debugging_p = false; } #endif /* ENABLE_CHECKING */ /* Create a new cp_token_cache, representing a range of tokens. */ static cp_token_cache * cp_token_cache_new (cp_token *first, cp_token *last) { cp_token_cache *cache = GGC_NEW (cp_token_cache); cache->first = first; cache->last = last; return cache; } /* Decl-specifiers. */ /* Set *DECL_SPECS to represent an empty decl-specifier-seq. */ static void clear_decl_specs (cp_decl_specifier_seq *decl_specs) { memset (decl_specs, 0, sizeof (cp_decl_specifier_seq)); } /* Declarators. */ /* Nothing other than the parser should be creating declarators; declarators are a semi-syntactic representation of C++ entities. Other parts of the front end that need to create entities (like VAR_DECLs or FUNCTION_DECLs) should do that directly. */ static cp_declarator *make_call_declarator (cp_declarator *, cp_parameter_declarator *, cp_cv_quals, tree); static cp_declarator *make_array_declarator (cp_declarator *, tree); static cp_declarator *make_pointer_declarator (cp_cv_quals, cp_declarator *); static cp_declarator *make_reference_declarator (cp_cv_quals, cp_declarator *, bool); static cp_parameter_declarator *make_parameter_declarator (cp_decl_specifier_seq *, cp_declarator *, tree); static cp_declarator *make_ptrmem_declarator (cp_cv_quals, tree, cp_declarator *); /* An erroneous declarator. */ static cp_declarator *cp_error_declarator; /* The obstack on which declarators and related data structures are allocated. */ static struct obstack declarator_obstack; /* Alloc BYTES from the declarator memory pool. */ static inline void * alloc_declarator (size_t bytes) { return obstack_alloc (&declarator_obstack, bytes); } /* Allocate a declarator of the indicated KIND. Clear fields that are common to all declarators. */ static cp_declarator * make_declarator (cp_declarator_kind kind) { cp_declarator *declarator; declarator = (cp_declarator *) alloc_declarator (sizeof (cp_declarator)); declarator->kind = kind; declarator->attributes = NULL_TREE; declarator->declarator = NULL; declarator->parameter_pack_p = false; return declarator; } /* Make a declarator for a generalized identifier. If QUALIFYING_SCOPE is non-NULL, the identifier is QUALIFYING_SCOPE::UNQUALIFIED_NAME; otherwise, it is just UNQUALIFIED_NAME. SFK indicates the kind of special function this is, if any. */ static cp_declarator * make_id_declarator (tree qualifying_scope, tree unqualified_name, special_function_kind sfk) { cp_declarator *declarator; /* It is valid to write: class C { void f(); }; typedef C D; void D::f(); The standard is not clear about whether `typedef const C D' is legal; as of 2002-09-15 the committee is considering that question. EDG 3.0 allows that syntax. Therefore, we do as well. */ if (qualifying_scope && TYPE_P (qualifying_scope)) qualifying_scope = TYPE_MAIN_VARIANT (qualifying_scope); gcc_assert (TREE_CODE (unqualified_name) == IDENTIFIER_NODE || TREE_CODE (unqualified_name) == BIT_NOT_EXPR || TREE_CODE (unqualified_name) == TEMPLATE_ID_EXPR); declarator = make_declarator (cdk_id); declarator->u.id.qualifying_scope = qualifying_scope; declarator->u.id.unqualified_name = unqualified_name; declarator->u.id.sfk = sfk; return declarator; } /* Make a declarator for a pointer to TARGET. CV_QUALIFIERS is a list of modifiers such as const or volatile to apply to the pointer type, represented as identifiers. */ cp_declarator * make_pointer_declarator (cp_cv_quals cv_qualifiers, cp_declarator *target) { cp_declarator *declarator; declarator = make_declarator (cdk_pointer); declarator->declarator = target; declarator->u.pointer.qualifiers = cv_qualifiers; declarator->u.pointer.class_type = NULL_TREE; if (target) { declarator->parameter_pack_p = target->parameter_pack_p; target->parameter_pack_p = false; } else declarator->parameter_pack_p = false; return declarator; } /* Like make_pointer_declarator -- but for references. */ cp_declarator * make_reference_declarator (cp_cv_quals cv_qualifiers, cp_declarator *target, bool rvalue_ref) { cp_declarator *declarator; declarator = make_declarator (cdk_reference); declarator->declarator = target; declarator->u.reference.qualifiers = cv_qualifiers; declarator->u.reference.rvalue_ref = rvalue_ref; if (target) { declarator->parameter_pack_p = target->parameter_pack_p; target->parameter_pack_p = false; } else declarator->parameter_pack_p = false; return declarator; } /* Like make_pointer_declarator -- but for a pointer to a non-static member of CLASS_TYPE. */ cp_declarator * make_ptrmem_declarator (cp_cv_quals cv_qualifiers, tree class_type, cp_declarator *pointee) { cp_declarator *declarator; declarator = make_declarator (cdk_ptrmem); declarator->declarator = pointee; declarator->u.pointer.qualifiers = cv_qualifiers; declarator->u.pointer.class_type = class_type; if (pointee) { declarator->parameter_pack_p = pointee->parameter_pack_p; pointee->parameter_pack_p = false; } else declarator->parameter_pack_p = false; return declarator; } /* Make a declarator for the function given by TARGET, with the indicated PARMS. The CV_QUALIFIERS aply to the function, as in "const"-qualified member function. The EXCEPTION_SPECIFICATION indicates what exceptions can be thrown. */ cp_declarator * make_call_declarator (cp_declarator *target, cp_parameter_declarator *parms, cp_cv_quals cv_qualifiers, tree exception_specification) { cp_declarator *declarator; declarator = make_declarator (cdk_function); declarator->declarator = target; declarator->u.function.parameters = parms; declarator->u.function.qualifiers = cv_qualifiers; declarator->u.function.exception_specification = exception_specification; if (target) { declarator->parameter_pack_p = target->parameter_pack_p; target->parameter_pack_p = false; } else declarator->parameter_pack_p = false; return declarator; } /* Make a declarator for an array of BOUNDS elements, each of which is defined by ELEMENT. */ cp_declarator * make_array_declarator (cp_declarator *element, tree bounds) { cp_declarator *declarator; declarator = make_declarator (cdk_array); declarator->declarator = element; declarator->u.array.bounds = bounds; if (element) { declarator->parameter_pack_p = element->parameter_pack_p; element->parameter_pack_p = false; } else declarator->parameter_pack_p = false; return declarator; } /* Determine whether the declarator we've seen so far can be a parameter pack, when followed by an ellipsis. */ static bool declarator_can_be_parameter_pack (cp_declarator *declarator) { /* Search for a declarator name, or any other declarator that goes after the point where the ellipsis could appear in a parameter pack. If we find any of these, then this declarator can not be made into a parameter pack. */ bool found = false; while (declarator && !found) { switch ((int)declarator->kind) { case cdk_id: case cdk_array: found = true; break; case cdk_error: return true; default: declarator = declarator->declarator; break; } } return !found; } cp_parameter_declarator *no_parameters; /* Create a parameter declarator with the indicated DECL_SPECIFIERS, DECLARATOR and DEFAULT_ARGUMENT. */ cp_parameter_declarator * make_parameter_declarator (cp_decl_specifier_seq *decl_specifiers, cp_declarator *declarator, tree default_argument) { cp_parameter_declarator *parameter; parameter = ((cp_parameter_declarator *) alloc_declarator (sizeof (cp_parameter_declarator))); parameter->next = NULL; if (decl_specifiers) parameter->decl_specifiers = *decl_specifiers; else clear_decl_specs (¶meter->decl_specifiers); parameter->declarator = declarator; parameter->default_argument = default_argument; parameter->ellipsis_p = false; return parameter; } /* Returns true iff DECLARATOR is a declaration for a function. */ static bool function_declarator_p (const cp_declarator *declarator) { while (declarator) { if (declarator->kind == cdk_function && declarator->declarator->kind == cdk_id) return true; if (declarator->kind == cdk_id || declarator->kind == cdk_error) return false; declarator = declarator->declarator; } return false; } /* The parser. */ /* Overview -------- A cp_parser parses the token stream as specified by the C++ grammar. Its job is purely parsing, not semantic analysis. For example, the parser breaks the token stream into declarators, expressions, statements, and other similar syntactic constructs. It does not check that the types of the expressions on either side of an assignment-statement are compatible, or that a function is not declared with a parameter of type `void'. The parser invokes routines elsewhere in the compiler to perform semantic analysis and to build up the abstract syntax tree for the code processed. The parser (and the template instantiation code, which is, in a way, a close relative of parsing) are the only parts of the compiler that should be calling push_scope and pop_scope, or related functions. The parser (and template instantiation code) keeps track of what scope is presently active; everything else should simply honor that. (The code that generates static initializers may also need to set the scope, in order to check access control correctly when emitting the initializers.) Methodology ----------- The parser is of the standard recursive-descent variety. Upcoming tokens in the token stream are examined in order to determine which production to use when parsing a non-terminal. Some C++ constructs require arbitrary look ahead to disambiguate. For example, it is impossible, in the general case, to tell whether a statement is an expression or declaration without scanning the entire statement. Therefore, the parser is capable of "parsing tentatively." When the parser is not sure what construct comes next, it enters this mode. Then, while we attempt to parse the construct, the parser queues up error messages, rather than issuing them immediately, and saves the tokens it consumes. If the construct is parsed successfully, the parser "commits", i.e., it issues any queued error messages and the tokens that were being preserved are permanently discarded. If, however, the construct is not parsed successfully, the parser rolls back its state completely so that it can resume parsing using a different alternative. Future Improvements ------------------- The performance of the parser could probably be improved substantially. We could often eliminate the need to parse tentatively by looking ahead a little bit. In some places, this approach might not entirely eliminate the need to parse tentatively, but it might still speed up the average case. */ /* Flags that are passed to some parsing functions. These values can be bitwise-ored together. */ typedef enum cp_parser_flags { /* No flags. */ CP_PARSER_FLAGS_NONE = 0x0, /* The construct is optional. If it is not present, then no error should be issued. */ CP_PARSER_FLAGS_OPTIONAL = 0x1, /* When parsing a type-specifier, do not allow user-defined types. */ CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES = 0x2 } cp_parser_flags; /* The different kinds of declarators we want to parse. */ typedef enum cp_parser_declarator_kind { /* We want an abstract declarator. */ CP_PARSER_DECLARATOR_ABSTRACT, /* We want a named declarator. */ CP_PARSER_DECLARATOR_NAMED, /* We don't mind, but the name must be an unqualified-id. */ CP_PARSER_DECLARATOR_EITHER } cp_parser_declarator_kind; /* The precedence values used to parse binary expressions. The minimum value of PREC must be 1, because zero is reserved to quickly discriminate binary operators from other tokens. */ enum cp_parser_prec { PREC_NOT_OPERATOR, PREC_LOGICAL_OR_EXPRESSION, PREC_LOGICAL_AND_EXPRESSION, PREC_INCLUSIVE_OR_EXPRESSION, PREC_EXCLUSIVE_OR_EXPRESSION, PREC_AND_EXPRESSION, PREC_EQUALITY_EXPRESSION, PREC_RELATIONAL_EXPRESSION, PREC_SHIFT_EXPRESSION, PREC_ADDITIVE_EXPRESSION, PREC_MULTIPLICATIVE_EXPRESSION, PREC_PM_EXPRESSION, NUM_PREC_VALUES = PREC_PM_EXPRESSION }; /* A mapping from a token type to a corresponding tree node type, with a precedence value. */ typedef struct cp_parser_binary_operations_map_node { /* The token type. */ enum cpp_ttype token_type; /* The corresponding tree code. */ enum tree_code tree_type; /* The precedence of this operator. */ enum cp_parser_prec prec; } cp_parser_binary_operations_map_node; /* The status of a tentative parse. */ typedef enum cp_parser_status_kind { /* No errors have occurred. */ CP_PARSER_STATUS_KIND_NO_ERROR, /* An error has occurred. */ CP_PARSER_STATUS_KIND_ERROR, /* We are committed to this tentative parse, whether or not an error has occurred. */ CP_PARSER_STATUS_KIND_COMMITTED } cp_parser_status_kind; typedef struct cp_parser_expression_stack_entry { /* Left hand side of the binary operation we are currently parsing. */ tree lhs; /* Original tree code for left hand side, if it was a binary expression itself (used for -Wparentheses). */ enum tree_code lhs_type; /* Tree code for the binary operation we are parsing. */ enum tree_code tree_type; /* Precedence of the binary operation we are parsing. */ int prec; } cp_parser_expression_stack_entry; /* The stack for storing partial expressions. We only need NUM_PREC_VALUES entries because precedence levels on the stack are monotonically increasing. */ typedef struct cp_parser_expression_stack_entry cp_parser_expression_stack[NUM_PREC_VALUES]; /* Context that is saved and restored when parsing tentatively. */ typedef struct cp_parser_context GTY (()) { /* If this is a tentative parsing context, the status of the tentative parse. */ enum cp_parser_status_kind status; /* If non-NULL, we have just seen a `x->' or `x.' expression. Names that are looked up in this context must be looked up both in the scope given by OBJECT_TYPE (the type of `x' or `*x') and also in the context of the containing expression. */ tree object_type; /* The next parsing context in the stack. */ struct cp_parser_context *next; } cp_parser_context; /* Prototypes. */ /* Constructors and destructors. */ static cp_parser_context *cp_parser_context_new (cp_parser_context *); /* Class variables. */ static GTY((deletable)) cp_parser_context* cp_parser_context_free_list; /* The operator-precedence table used by cp_parser_binary_expression. Transformed into an associative array (binops_by_token) by cp_parser_new. */ static const cp_parser_binary_operations_map_node binops[] = { { CPP_DEREF_STAR, MEMBER_REF, PREC_PM_EXPRESSION }, { CPP_DOT_STAR, DOTSTAR_EXPR, PREC_PM_EXPRESSION }, { CPP_MULT, MULT_EXPR, PREC_MULTIPLICATIVE_EXPRESSION }, { CPP_DIV, TRUNC_DIV_EXPR, PREC_MULTIPLICATIVE_EXPRESSION }, { CPP_MOD, TRUNC_MOD_EXPR, PREC_MULTIPLICATIVE_EXPRESSION }, { CPP_PLUS, PLUS_EXPR, PREC_ADDITIVE_EXPRESSION }, { CPP_MINUS, MINUS_EXPR, PREC_ADDITIVE_EXPRESSION }, { CPP_LSHIFT, LSHIFT_EXPR, PREC_SHIFT_EXPRESSION }, { CPP_RSHIFT, RSHIFT_EXPR, PREC_SHIFT_EXPRESSION }, { CPP_LESS, LT_EXPR, PREC_RELATIONAL_EXPRESSION }, { CPP_GREATER, GT_EXPR, PREC_RELATIONAL_EXPRESSION }, { CPP_LESS_EQ, LE_EXPR, PREC_RELATIONAL_EXPRESSION }, { CPP_GREATER_EQ, GE_EXPR, PREC_RELATIONAL_EXPRESSION }, { CPP_EQ_EQ, EQ_EXPR, PREC_EQUALITY_EXPRESSION }, { CPP_NOT_EQ, NE_EXPR, PREC_EQUALITY_EXPRESSION }, { CPP_AND, BIT_AND_EXPR, PREC_AND_EXPRESSION }, { CPP_XOR, BIT_XOR_EXPR, PREC_EXCLUSIVE_OR_EXPRESSION }, { CPP_OR, BIT_IOR_EXPR, PREC_INCLUSIVE_OR_EXPRESSION }, { CPP_AND_AND, TRUTH_ANDIF_EXPR, PREC_LOGICAL_AND_EXPRESSION }, { CPP_OR_OR, TRUTH_ORIF_EXPR, PREC_LOGICAL_OR_EXPRESSION } }; /* The same as binops, but initialized by cp_parser_new so that binops_by_token[N].token_type == N. Used in cp_parser_binary_expression for speed. */ static cp_parser_binary_operations_map_node binops_by_token[N_CP_TTYPES]; /* Constructors and destructors. */ /* Construct a new context. The context below this one on the stack is given by NEXT. */ static cp_parser_context * cp_parser_context_new (cp_parser_context* next) { cp_parser_context *context; /* Allocate the storage. */ if (cp_parser_context_free_list != NULL) { /* Pull the first entry from the free list. */ context = cp_parser_context_free_list; cp_parser_context_free_list = context->next; memset (context, 0, sizeof (*context)); } else context = GGC_CNEW (cp_parser_context); /* No errors have occurred yet in this context. */ context->status = CP_PARSER_STATUS_KIND_NO_ERROR; /* If this is not the bottomost context, copy information that we need from the previous context. */ if (next) { /* If, in the NEXT context, we are parsing an `x->' or `x.' expression, then we are parsing one in this context, too. */ context->object_type = next->object_type; /* Thread the stack. */ context->next = next; } return context; } /* The cp_parser structure represents the C++ parser. */ typedef struct cp_parser GTY(()) { /* The lexer from which we are obtaining tokens. */ cp_lexer *lexer; /* The scope in which names should be looked up. If NULL_TREE, then we look up names in the scope that is currently open in the source program. If non-NULL, this is either a TYPE or NAMESPACE_DECL for the scope in which we should look. It can also be ERROR_MARK, when we've parsed a bogus scope. This value is not cleared automatically after a name is looked up, so we must be careful to clear it before starting a new look up sequence. (If it is not cleared, then `X::Y' followed by `Z' will look up `Z' in the scope of `X', rather than the current scope.) Unfortunately, it is difficult to tell when name lookup is complete, because we sometimes peek at a token, look it up, and then decide not to consume it. */ tree scope; /* OBJECT_SCOPE and QUALIFYING_SCOPE give the scopes in which the last lookup took place. OBJECT_SCOPE is used if an expression like "x->y" or "x.y" was used; it gives the type of "*x" or "x", respectively. QUALIFYING_SCOPE is used for an expression of the form "X::Y"; it refers to X. */ tree object_scope; tree qualifying_scope; /* A stack of parsing contexts. All but the bottom entry on the stack will be tentative contexts. We parse tentatively in order to determine which construct is in use in some situations. For example, in order to determine whether a statement is an expression-statement or a declaration-statement we parse it tentatively as a declaration-statement. If that fails, we then reparse the same token stream as an expression-statement. */ cp_parser_context *context; /* True if we are parsing GNU C++. If this flag is not set, then GNU extensions are not recognized. */ bool allow_gnu_extensions_p; /* TRUE if the `>' token should be interpreted as the greater-than operator. FALSE if it is the end of a template-id or template-parameter-list. In C++0x mode, this flag also applies to `>>' tokens, which are viewed as two consecutive `>' tokens when this flag is FALSE. */ bool greater_than_is_operator_p; /* TRUE if default arguments are allowed within a parameter list that starts at this point. FALSE if only a gnu extension makes them permissible. */ bool default_arg_ok_p; /* TRUE if we are parsing an integral constant-expression. See [expr.const] for a precise definition. */ bool integral_constant_expression_p; /* TRUE if we are parsing an integral constant-expression -- but a non-constant expression should be permitted as well. This flag is used when parsing an array bound so that GNU variable-length arrays are tolerated. */ bool allow_non_integral_constant_expression_p; /* TRUE if ALLOW_NON_CONSTANT_EXPRESSION_P is TRUE and something has been seen that makes the expression non-constant. */ bool non_integral_constant_expression_p; /* TRUE if local variable names and `this' are forbidden in the current context. */ bool local_variables_forbidden_p; /* TRUE if the declaration we are parsing is part of a linkage-specification of the form `extern string-literal declaration'. */ bool in_unbraced_linkage_specification_p; /* TRUE if we are presently parsing a declarator, after the direct-declarator. */ bool in_declarator_p; /* TRUE if we are presently parsing a template-argument-list. */ bool in_template_argument_list_p; /* Set to IN_ITERATION_STMT if parsing an iteration-statement, to IN_OMP_BLOCK if parsing OpenMP structured block and IN_OMP_FOR if parsing OpenMP loop. If parsing a switch statement, this is bitwise ORed with IN_SWITCH_STMT, unless parsing an iteration-statement, OpenMP block or loop within that switch. */ #define IN_SWITCH_STMT 1 #define IN_ITERATION_STMT 2 #define IN_OMP_BLOCK 4 #define IN_OMP_FOR 8 #define IN_IF_STMT 16 unsigned char in_statement; /* TRUE if we are presently parsing the body of a switch statement. Note that this doesn't quite overlap with in_statement above. The difference relates to giving the right sets of error messages: "case not in switch" vs "break statement used with OpenMP...". */ bool in_switch_statement_p; /* TRUE if we are parsing a type-id in an expression context. In such a situation, both "type (expr)" and "type (type)" are valid alternatives. */ bool in_type_id_in_expr_p; /* TRUE if we are currently in a header file where declarations are implicitly extern "C". */ bool implicit_extern_c; /* TRUE if strings in expressions should be translated to the execution character set. */ bool translate_strings_p; /* TRUE if we are presently parsing the body of a function, but not a local class. */ bool in_function_body; /* If non-NULL, then we are parsing a construct where new type definitions are not permitted. The string stored here will be issued as an error message if a type is defined. */ const char *type_definition_forbidden_message; /* A list of lists. The outer list is a stack, used for member functions of local classes. At each level there are two sub-list, one on TREE_VALUE and one on TREE_PURPOSE. Each of those sub-lists has a FUNCTION_DECL or TEMPLATE_DECL on their TREE_VALUE's. The functions are chained in reverse declaration order. The TREE_PURPOSE sublist contains those functions with default arguments that need post processing, and the TREE_VALUE sublist contains those functions with definitions that need post processing. These lists can only be processed once the outermost class being defined is complete. */ tree unparsed_functions_queues; /* The number of classes whose definitions are currently in progress. */ unsigned num_classes_being_defined; /* The number of template parameter lists that apply directly to the current declaration. */ unsigned num_template_parameter_lists; } cp_parser; /* Prototypes. */ /* Constructors and destructors. */ static cp_parser *cp_parser_new (void); /* Routines to parse various constructs. Those that return `tree' will return the error_mark_node (rather than NULL_TREE) if a parse error occurs, unless otherwise noted. Sometimes, they will return an ordinary node if error-recovery was attempted, even though a parse error occurred. So, to check whether or not a parse error occurred, you should always use cp_parser_error_occurred. If the construct is optional (indicated either by an `_opt' in the name of the function that does the parsing or via a FLAGS parameter), then NULL_TREE is returned if the construct is not present. */ /* Lexical conventions [gram.lex] */ static tree cp_parser_identifier (cp_parser *); static tree cp_parser_string_literal (cp_parser *, bool, bool); /* Basic concepts [gram.basic] */ static bool cp_parser_translation_unit (cp_parser *); /* Expressions [gram.expr] */ static tree cp_parser_primary_expression (cp_parser *, bool, bool, bool, cp_id_kind *); static tree cp_parser_id_expression (cp_parser *, bool, bool, bool *, bool, bool); static tree cp_parser_unqualified_id (cp_parser *, bool, bool, bool, bool); static tree cp_parser_nested_name_specifier_opt (cp_parser *, bool, bool, bool, bool); static tree cp_parser_nested_name_specifier (cp_parser *, bool, bool, bool, bool); static tree cp_parser_class_or_namespace_name (cp_parser *, bool, bool, bool, bool, bool); static tree cp_parser_postfix_expression (cp_parser *, bool, bool, bool); static tree cp_parser_postfix_open_square_expression (cp_parser *, tree, bool); static tree cp_parser_postfix_dot_deref_expression (cp_parser *, enum cpp_ttype, tree, bool, cp_id_kind *); static tree cp_parser_parenthesized_expression_list (cp_parser *, bool, bool, bool, bool *); static void cp_parser_pseudo_destructor_name (cp_parser *, tree *, tree *); static tree cp_parser_unary_expression (cp_parser *, bool, bool); static enum tree_code cp_parser_unary_operator (cp_token *); static tree cp_parser_new_expression (cp_parser *); static tree cp_parser_new_placement (cp_parser *); static tree cp_parser_new_type_id (cp_parser *, tree *); static cp_declarator *cp_parser_new_declarator_opt (cp_parser *); static cp_declarator *cp_parser_direct_new_declarator (cp_parser *); static tree cp_parser_new_initializer (cp_parser *); static tree cp_parser_delete_expression (cp_parser *); static tree cp_parser_cast_expression (cp_parser *, bool, bool); static tree cp_parser_binary_expression (cp_parser *, bool); static tree cp_parser_question_colon_clause (cp_parser *, tree); static tree cp_parser_assignment_expression (cp_parser *, bool); static enum tree_code cp_parser_assignment_operator_opt (cp_parser *); static tree cp_parser_expression (cp_parser *, bool); static tree cp_parser_constant_expression (cp_parser *, bool, bool *); static tree cp_parser_builtin_offsetof (cp_parser *); /* Statements [gram.stmt.stmt] */ static void cp_parser_statement (cp_parser *, tree, bool, bool *); static void cp_parser_label_for_labeled_statement (cp_parser *); static tree cp_parser_expression_statement (cp_parser *, tree); static tree cp_parser_compound_statement (cp_parser *, tree, bool); static void cp_parser_statement_seq_opt (cp_parser *, tree); static tree cp_parser_selection_statement (cp_parser *, bool *); static tree cp_parser_condition (cp_parser *); static tree cp_parser_iteration_statement (cp_parser *); static void cp_parser_for_init_statement (cp_parser *); static tree cp_parser_jump_statement (cp_parser *); static void cp_parser_declaration_statement (cp_parser *); static tree cp_parser_implicitly_scoped_statement (cp_parser *, bool *); static void cp_parser_already_scoped_statement (cp_parser *); /* Declarations [gram.dcl.dcl] */ static void cp_parser_declaration_seq_opt (cp_parser *); static void cp_parser_declaration (cp_parser *); static void cp_parser_block_declaration (cp_parser *, bool); static void cp_parser_simple_declaration (cp_parser *, bool); static void cp_parser_decl_specifier_seq (cp_parser *, cp_parser_flags, cp_decl_specifier_seq *, int *); static tree cp_parser_storage_class_specifier_opt (cp_parser *); static tree cp_parser_function_specifier_opt (cp_parser *, cp_decl_specifier_seq *); static tree cp_parser_type_specifier (cp_parser *, cp_parser_flags, cp_decl_specifier_seq *, bool, int *, bool *); static tree cp_parser_simple_type_specifier (cp_parser *, cp_decl_specifier_seq *, cp_parser_flags); static tree cp_parser_type_name (cp_parser *); static tree cp_parser_nonclass_name (cp_parser* parser); static tree cp_parser_elaborated_type_specifier (cp_parser *, bool, bool); static tree cp_parser_enum_specifier (cp_parser *); static void cp_parser_enumerator_list (cp_parser *, tree); static void cp_parser_enumerator_definition (cp_parser *, tree); static tree cp_parser_namespace_name (cp_parser *); static void cp_parser_namespace_definition (cp_parser *); static void cp_parser_namespace_body (cp_parser *); static tree cp_parser_qualified_namespace_specifier (cp_parser *); static void cp_parser_namespace_alias_definition (cp_parser *); static bool cp_parser_using_declaration (cp_parser *, bool); static void cp_parser_using_directive (cp_parser *); static void cp_parser_asm_definition (cp_parser *); static void cp_parser_linkage_specification (cp_parser *); static void cp_parser_static_assert (cp_parser *, bool); static tree cp_parser_decltype (cp_parser *); /* Declarators [gram.dcl.decl] */ static tree cp_parser_init_declarator (cp_parser *, cp_decl_specifier_seq *, VEC (deferred_access_check,gc)*, bool, bool, int, bool *); static cp_declarator *cp_parser_declarator (cp_parser *, cp_parser_declarator_kind, int *, bool *, bool); static cp_declarator *cp_parser_direct_declarator (cp_parser *, cp_parser_declarator_kind, int *, bool); static enum tree_code cp_parser_ptr_operator (cp_parser *, tree *, cp_cv_quals *); static cp_cv_quals cp_parser_cv_qualifier_seq_opt (cp_parser *); static tree cp_parser_declarator_id (cp_parser *, bool); static tree cp_parser_type_id (cp_parser *); static void cp_parser_type_specifier_seq (cp_parser *, bool, cp_decl_specifier_seq *); static cp_parameter_declarator *cp_parser_parameter_declaration_clause (cp_parser *); static cp_parameter_declarator *cp_parser_parameter_declaration_list (cp_parser *, bool *); static cp_parameter_declarator *cp_parser_parameter_declaration (cp_parser *, bool, bool *); static tree cp_parser_default_argument (cp_parser *, bool); static void cp_parser_function_body (cp_parser *); static tree cp_parser_initializer (cp_parser *, bool *, bool *); static tree cp_parser_initializer_clause (cp_parser *, bool *); static VEC(constructor_elt,gc) *cp_parser_initializer_list (cp_parser *, bool *); static bool cp_parser_ctor_initializer_opt_and_function_body (cp_parser *); /* Classes [gram.class] */ static tree cp_parser_class_name (cp_parser *, bool, bool, enum tag_types, bool, bool, bool); static tree cp_parser_class_specifier (cp_parser *); static tree cp_parser_class_head (cp_parser *, bool *, tree *, tree *); static enum tag_types cp_parser_class_key (cp_parser *); static void cp_parser_member_specification_opt (cp_parser *); static void cp_parser_member_declaration (cp_parser *); static tree cp_parser_pure_specifier (cp_parser *); static tree cp_parser_constant_initializer (cp_parser *); /* Derived classes [gram.class.derived] */ static tree cp_parser_base_clause (cp_parser *); static tree cp_parser_base_specifier (cp_parser *); /* Special member functions [gram.special] */ static tree cp_parser_conversion_function_id (cp_parser *); static tree cp_parser_conversion_type_id (cp_parser *); static cp_declarator *cp_parser_conversion_declarator_opt (cp_parser *); static bool cp_parser_ctor_initializer_opt (cp_parser *); static void cp_parser_mem_initializer_list (cp_parser *); static tree cp_parser_mem_initializer (cp_parser *); static tree cp_parser_mem_initializer_id (cp_parser *); /* Overloading [gram.over] */ static tree cp_parser_operator_function_id (cp_parser *); static tree cp_parser_operator (cp_parser *); /* Templates [gram.temp] */ static void cp_parser_template_declaration (cp_parser *, bool); static tree cp_parser_template_parameter_list (cp_parser *); static tree cp_parser_template_parameter (cp_parser *, bool *, bool *); static tree cp_parser_type_parameter (cp_parser *, bool *); static tree cp_parser_template_id (cp_parser *, bool, bool, bool); static tree cp_parser_template_name (cp_parser *, bool, bool, bool, bool *); static tree cp_parser_template_argument_list (cp_parser *); static tree cp_parser_template_argument (cp_parser *); static void cp_parser_explicit_instantiation (cp_parser *); static void cp_parser_explicit_specialization (cp_parser *); /* Exception handling [gram.exception] */ static tree cp_parser_try_block (cp_parser *); static bool cp_parser_function_try_block (cp_parser *); static void cp_parser_handler_seq (cp_parser *); static void cp_parser_handler (cp_parser *); static tree cp_parser_exception_declaration (cp_parser *); static tree cp_parser_throw_expression (cp_parser *); static tree cp_parser_exception_specification_opt (cp_parser *); static tree cp_parser_type_id_list (cp_parser *); /* GNU Extensions */ static tree cp_parser_asm_specification_opt (cp_parser *); static tree cp_parser_asm_operand_list (cp_parser *); static tree cp_parser_asm_clobber_list (cp_parser *); static tree cp_parser_attributes_opt (cp_parser *); static tree cp_parser_attribute_list (cp_parser *); static bool cp_parser_extension_opt (cp_parser *, int *); static void cp_parser_label_declaration (cp_parser *); enum pragma_context { pragma_external, pragma_stmt, pragma_compound }; static bool cp_parser_pragma (cp_parser *, enum pragma_context); /* Objective-C++ Productions */ static tree cp_parser_objc_message_receiver (cp_parser *); static tree cp_parser_objc_message_args (cp_parser *); static tree cp_parser_objc_message_expression (cp_parser *); static tree cp_parser_objc_encode_expression (cp_parser *); static tree cp_parser_objc_defs_expression (cp_parser *); static tree cp_parser_objc_protocol_expression (cp_parser *); static tree cp_parser_objc_selector_expression (cp_parser *); static tree cp_parser_objc_expression (cp_parser *); static bool cp_parser_objc_selector_p (enum cpp_ttype); static tree cp_parser_objc_selector (cp_parser *); static tree cp_parser_objc_protocol_refs_opt (cp_parser *); static void cp_parser_objc_declaration (cp_parser *); static tree cp_parser_objc_statement (cp_parser *); /* Utility Routines */ static tree cp_parser_lookup_name (cp_parser *, tree, enum tag_types, bool, bool, bool, tree *); static tree cp_parser_lookup_name_simple (cp_parser *, tree); static tree cp_parser_maybe_treat_template_as_class (tree, bool); static bool cp_parser_check_declarator_template_parameters (cp_parser *, cp_declarator *); static bool cp_parser_check_template_parameters (cp_parser *, unsigned); static tree cp_parser_simple_cast_expression (cp_parser *); static tree cp_parser_global_scope_opt (cp_parser *, bool); static bool cp_parser_constructor_declarator_p (cp_parser *, bool); static tree cp_parser_function_definition_from_specifiers_and_declarator (cp_parser *, cp_decl_specifier_seq *, tree, const cp_declarator *); static tree cp_parser_function_definition_after_declarator (cp_parser *, bool); static void cp_parser_template_declaration_after_export (cp_parser *, bool); static void cp_parser_perform_template_parameter_access_checks (VEC (deferred_access_check,gc)*); static tree cp_parser_single_declaration (cp_parser *, VEC (deferred_access_check,gc)*, bool, bool, bool *); static tree cp_parser_functional_cast (cp_parser *, tree); static tree cp_parser_save_member_function_body (cp_parser *, cp_decl_specifier_seq *, cp_declarator *, tree); static tree cp_parser_enclosed_template_argument_list (cp_parser *); static void cp_parser_save_default_args (cp_parser *, tree); static void cp_parser_late_parsing_for_member (cp_parser *, tree); static void cp_parser_late_parsing_default_args (cp_parser *, tree); static tree cp_parser_sizeof_operand (cp_parser *, enum rid); static tree cp_parser_trait_expr (cp_parser *, enum rid); static bool cp_parser_declares_only_class_p (cp_parser *); static void cp_parser_set_storage_class (cp_parser *, cp_decl_specifier_seq *, enum rid); static void cp_parser_set_decl_spec_type (cp_decl_specifier_seq *, tree, bool); static bool cp_parser_friend_p (const cp_decl_specifier_seq *); static cp_token *cp_parser_require (cp_parser *, enum cpp_ttype, const char *); static cp_token *cp_parser_require_keyword (cp_parser *, enum rid, const char *); static bool cp_parser_token_starts_function_definition_p (cp_token *); static bool cp_parser_next_token_starts_class_definition_p (cp_parser *); static bool cp_parser_next_token_ends_template_argument_p (cp_parser *); static bool cp_parser_nth_token_starts_template_argument_list_p (cp_parser *, size_t); static enum tag_types cp_parser_token_is_class_key (cp_token *); static void cp_parser_check_class_key (enum tag_types, tree type); static void cp_parser_check_access_in_redeclaration (tree type); static bool cp_parser_optional_template_keyword (cp_parser *); static void cp_parser_pre_parsed_nested_name_specifier (cp_parser *); static void cp_parser_cache_group (cp_parser *, enum cpp_ttype, unsigned); static void cp_parser_parse_tentatively (cp_parser *); static void cp_parser_commit_to_tentative_parse (cp_parser *); static void cp_parser_abort_tentative_parse (cp_parser *); static bool cp_parser_parse_definitely (cp_parser *); static inline bool cp_parser_parsing_tentatively (cp_parser *); static bool cp_parser_uncommitted_to_tentative_parse_p (cp_parser *); static void cp_parser_error (cp_parser *, const char *); static void cp_parser_name_lookup_error (cp_parser *, tree, tree, const char *); static bool cp_parser_simulate_error (cp_parser *); static bool cp_parser_check_type_definition (cp_parser *); static void cp_parser_check_for_definition_in_return_type (cp_declarator *, tree); static void cp_parser_check_for_invalid_template_id (cp_parser *, tree); static bool cp_parser_non_integral_constant_expression (cp_parser *, const char *); static void cp_parser_diagnose_invalid_type_name (cp_parser *, tree, tree); static bool cp_parser_parse_and_diagnose_invalid_type_name (cp_parser *); static int cp_parser_skip_to_closing_parenthesis (cp_parser *, bool, bool, bool); static void cp_parser_skip_to_end_of_statement (cp_parser *); static void cp_parser_consume_semicolon_at_end_of_statement (cp_parser *); static void cp_parser_skip_to_end_of_block_or_statement (cp_parser *); static bool cp_parser_skip_to_closing_brace (cp_parser *); static void cp_parser_skip_to_end_of_template_parameter_list (cp_parser *); static void cp_parser_skip_to_pragma_eol (cp_parser*, cp_token *); static bool cp_parser_error_occurred (cp_parser *); static bool cp_parser_allow_gnu_extensions_p (cp_parser *); static bool cp_parser_is_string_literal (cp_token *); static bool cp_parser_is_keyword (cp_token *, enum rid); static tree cp_parser_make_typename_type (cp_parser *, tree, tree); static cp_declarator * cp_parser_make_indirect_declarator (enum tree_code, tree, cp_cv_quals, cp_declarator *); /* Returns nonzero if we are parsing tentatively. */ static inline bool cp_parser_parsing_tentatively (cp_parser* parser) { return parser->context->next != NULL; } /* Returns nonzero if TOKEN is a string literal. */ static bool cp_parser_is_string_literal (cp_token* token) { return (token->type == CPP_STRING || token->type == CPP_WSTRING); } /* Returns nonzero if TOKEN is the indicated KEYWORD. */ static bool cp_parser_is_keyword (cp_token* token, enum rid keyword) { return token->keyword == keyword; } /* If not parsing tentatively, issue a diagnostic of the form FILE:LINE: MESSAGE before TOKEN where TOKEN is the next token in the input stream. MESSAGE (specified by the caller) is usually of the form "expected OTHER-TOKEN". */ static void cp_parser_error (cp_parser* parser, const char* message) { if (!cp_parser_simulate_error (parser)) { cp_token *token = cp_lexer_peek_token (parser->lexer); /* This diagnostic makes more sense if it is tagged to the line of the token we just peeked at. */ cp_lexer_set_source_position_from_token (token); if (token->type == CPP_PRAGMA) { error ("%<#pragma%> is not allowed here"); cp_parser_skip_to_pragma_eol (parser, token); return; } c_parse_error (message, /* Because c_parser_error does not understand CPP_KEYWORD, keywords are treated like identifiers. */ (token->type == CPP_KEYWORD ? CPP_NAME : token->type), token->u.value); } } /* Issue an error about name-lookup failing. NAME is the IDENTIFIER_NODE DECL is the result of the lookup (as returned from cp_parser_lookup_name). DESIRED is the thing that we hoped to find. */ static void cp_parser_name_lookup_error (cp_parser* parser, tree name, tree decl, const char* desired) { /* If name lookup completely failed, tell the user that NAME was not declared. */ if (decl == error_mark_node) { if (parser->scope && parser->scope != global_namespace) error ("%<%E::%E%> has not been declared", parser->scope, name); else if (parser->scope == global_namespace) error ("%<::%E%> has not been declared", name); else if (parser->object_scope && !CLASS_TYPE_P (parser->object_scope)) error ("request for member %qE in non-class type %qT", name, parser->object_scope); else if (parser->object_scope) error ("%<%T::%E%> has not been declared", parser->object_scope, name); else error ("%qE has not been declared", name); } else if (parser->scope && parser->scope != global_namespace) error ("%<%E::%E%> %s", parser->scope, name, desired); else if (parser->scope == global_namespace) error ("%<::%E%> %s", name, desired); else error ("%qE %s", name, desired); } /* If we are parsing tentatively, remember that an error has occurred during this tentative parse. Returns true if the error was simulated; false if a message should be issued by the caller. */ static bool cp_parser_simulate_error (cp_parser* parser) { if (cp_parser_uncommitted_to_tentative_parse_p (parser)) { parser->context->status = CP_PARSER_STATUS_KIND_ERROR; return true; } return false; } /* Check for repeated decl-specifiers. */ static void cp_parser_check_decl_spec (cp_decl_specifier_seq *decl_specs) { cp_decl_spec ds; for (ds = ds_first; ds != ds_last; ++ds) { unsigned count = decl_specs->specs[(int)ds]; if (count < 2) continue; /* The "long" specifier is a special case because of "long long". */ if (ds == ds_long) { if (count > 2) error ("% is too long for GCC"); else if (pedantic && !in_system_header && warn_long_long && cxx_dialect == cxx98) pedwarn ("ISO C++ 1998 does not support %"); } else if (count > 1) { static const char *const decl_spec_names[] = { "signed", "unsigned", "short", "long", "const", "volatile", "restrict", "inline", "virtual", "explicit", "friend", "typedef", "__complex", "__thread" }; error ("duplicate %qs", decl_spec_names[(int)ds]); } } } /* This function is called when a type is defined. If type definitions are forbidden at this point, an error message is issued. */ static bool cp_parser_check_type_definition (cp_parser* parser) { /* If types are forbidden here, issue a message. */ if (parser->type_definition_forbidden_message) { /* Use `%s' to print the string in case there are any escape characters in the message. */ error ("%s", parser->type_definition_forbidden_message); return false; } return true; } /* This function is called when the DECLARATOR is processed. The TYPE was a type defined in the decl-specifiers. If it is invalid to define a type in the decl-specifiers for DECLARATOR, an error is issued. */ static void cp_parser_check_for_definition_in_return_type (cp_declarator *declarator, tree type) { /* [dcl.fct] forbids type definitions in return types. Unfortunately, it's not easy to know whether or not we are processing a return type until after the fact. */ while (declarator && (declarator->kind == cdk_pointer || declarator->kind == cdk_reference || declarator->kind == cdk_ptrmem)) declarator = declarator->declarator; if (declarator && declarator->kind == cdk_function) { error ("new types may not be defined in a return type"); inform ("(perhaps a semicolon is missing after the definition of %qT)", type); } } /* A type-specifier (TYPE) has been parsed which cannot be followed by "<" in any valid C++ program. If the next token is indeed "<", issue a message warning the user about what appears to be an invalid attempt to form a template-id. */ static void cp_parser_check_for_invalid_template_id (cp_parser* parser, tree type) { cp_token_position start = 0; if (cp_lexer_next_token_is (parser->lexer, CPP_LESS)) { if (TYPE_P (type)) error ("%qT is not a template", type); else if (TREE_CODE (type) == IDENTIFIER_NODE) error ("%qE is not a template", type); else error ("invalid template-id"); /* Remember the location of the invalid "<". */ if (cp_parser_uncommitted_to_tentative_parse_p (parser)) start = cp_lexer_token_position (parser->lexer, true); /* Consume the "<". */ cp_lexer_consume_token (parser->lexer); /* Parse the template arguments. */ cp_parser_enclosed_template_argument_list (parser); /* Permanently remove the invalid template arguments so that this error message is not issued again. */ if (start) cp_lexer_purge_tokens_after (parser->lexer, start); } } /* If parsing an integral constant-expression, issue an error message about the fact that THING appeared and return true. Otherwise, return false. In either case, set PARSER->NON_INTEGRAL_CONSTANT_EXPRESSION_P. */ static bool cp_parser_non_integral_constant_expression (cp_parser *parser, const char *thing) { parser->non_integral_constant_expression_p = true; if (parser->integral_constant_expression_p) { if (!parser->allow_non_integral_constant_expression_p) { error ("%s cannot appear in a constant-expression", thing); return true; } } return false; } /* Emit a diagnostic for an invalid type name. SCOPE is the qualifying scope (or NULL, if none) for ID. This function commits to the current active tentative parse, if any. (Otherwise, the problematic construct might be encountered again later, resulting in duplicate error messages.) */ static void cp_parser_diagnose_invalid_type_name (cp_parser *parser, tree scope, tree id) { tree decl, old_scope; /* Try to lookup the identifier. */ old_scope = parser->scope; parser->scope = scope; decl = cp_parser_lookup_name_simple (parser, id); parser->scope = old_scope; /* If the lookup found a template-name, it means that the user forgot to specify an argument list. Emit a useful error message. */ if (TREE_CODE (decl) == TEMPLATE_DECL) error ("invalid use of template-name %qE without an argument list", decl); else if (TREE_CODE (id) == BIT_NOT_EXPR) error ("invalid use of destructor %qD as a type", id); else if (TREE_CODE (decl) == TYPE_DECL) /* Something like 'unsigned A a;' */ error ("invalid combination of multiple type-specifiers"); else if (!parser->scope) { /* Issue an error message. */ error ("%qE does not name a type", id); /* If we're in a template class, it's possible that the user was referring to a type from a base class. For example: template struct A { typedef T X; }; template struct B : public A { X x; }; The user should have said "typename A::X". */ if (processing_template_decl && current_class_type && TYPE_BINFO (current_class_type)) { tree b; for (b = TREE_CHAIN (TYPE_BINFO (current_class_type)); b; b = TREE_CHAIN (b)) { tree base_type = BINFO_TYPE (b); if (CLASS_TYPE_P (base_type) && dependent_type_p (base_type)) { tree field; /* Go from a particular instantiation of the template (which will have an empty TYPE_FIELDs), to the main version. */ base_type = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (base_type); for (field = TYPE_FIELDS (base_type); field; field = TREE_CHAIN (field)) if (TREE_CODE (field) == TYPE_DECL && DECL_NAME (field) == id) { inform ("(perhaps % was intended)", BINFO_TYPE (b), id); break; } if (field) break; } } } } /* Here we diagnose qualified-ids where the scope is actually correct, but the identifier does not resolve to a valid type name. */ else if (parser->scope != error_mark_node) { if (TREE_CODE (parser->scope) == NAMESPACE_DECL) error ("%qE in namespace %qE does not name a type", id, parser->scope); else if (TYPE_P (parser->scope)) error ("%qE in class %qT does not name a type", id, parser->scope); else gcc_unreachable (); } cp_parser_commit_to_tentative_parse (parser); } /* Check for a common situation where a type-name should be present, but is not, and issue a sensible error message. Returns true if an invalid type-name was detected. The situation handled by this function are variable declarations of the form `ID a', where `ID' is an id-expression and `a' is a plain identifier. Usually, `ID' should name a type, but if we got here it means that it does not. We try to emit the best possible error message depending on how exactly the id-expression looks like. */ static bool cp_parser_parse_and_diagnose_invalid_type_name (cp_parser *parser) { tree id; cp_parser_parse_tentatively (parser); id = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*template_p=*/NULL, /*declarator_p=*/true, /*optional_p=*/false); /* After the id-expression, there should be a plain identifier, otherwise this is not a simple variable declaration. Also, if the scope is dependent, we cannot do much. */ if (!cp_lexer_next_token_is (parser->lexer, CPP_NAME) || (parser->scope && TYPE_P (parser->scope) && dependent_type_p (parser->scope)) || TREE_CODE (id) == TYPE_DECL) { cp_parser_abort_tentative_parse (parser); return false; } if (!cp_parser_parse_definitely (parser)) return false; /* Emit a diagnostic for the invalid type. */ cp_parser_diagnose_invalid_type_name (parser, parser->scope, id); /* Skip to the end of the declaration; there's no point in trying to process it. */ cp_parser_skip_to_end_of_block_or_statement (parser); return true; } /* Consume tokens up to, and including, the next non-nested closing `)'. Returns 1 iff we found a closing `)'. RECOVERING is true, if we are doing error recovery. Returns -1 if OR_COMMA is true and we found an unnested comma. */ static int cp_parser_skip_to_closing_parenthesis (cp_parser *parser, bool recovering, bool or_comma, bool consume_paren) { unsigned paren_depth = 0; unsigned brace_depth = 0; if (recovering && !or_comma && cp_parser_uncommitted_to_tentative_parse_p (parser)) return 0; while (true) { cp_token * token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_EOF: case CPP_PRAGMA_EOL: /* If we've run out of tokens, then there is no closing `)'. */ return 0; case CPP_SEMICOLON: /* This matches the processing in skip_to_end_of_statement. */ if (!brace_depth) return 0; break; case CPP_OPEN_BRACE: ++brace_depth; break; case CPP_CLOSE_BRACE: if (!brace_depth--) return 0; break; case CPP_COMMA: if (recovering && or_comma && !brace_depth && !paren_depth) return -1; break; case CPP_OPEN_PAREN: if (!brace_depth) ++paren_depth; break; case CPP_CLOSE_PAREN: if (!brace_depth && !paren_depth--) { if (consume_paren) cp_lexer_consume_token (parser->lexer); return 1; } break; default: break; } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* Consume tokens until we reach the end of the current statement. Normally, that will be just before consuming a `;'. However, if a non-nested `}' comes first, then we stop before consuming that. */ static void cp_parser_skip_to_end_of_statement (cp_parser* parser) { unsigned nesting_depth = 0; while (true) { cp_token *token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_EOF: case CPP_PRAGMA_EOL: /* If we've run out of tokens, stop. */ return; case CPP_SEMICOLON: /* If the next token is a `;', we have reached the end of the statement. */ if (!nesting_depth) return; break; case CPP_CLOSE_BRACE: /* If this is a non-nested '}', stop before consuming it. That way, when confronted with something like: { 3 + } we stop before consuming the closing '}', even though we have not yet reached a `;'. */ if (nesting_depth == 0) return; /* If it is the closing '}' for a block that we have scanned, stop -- but only after consuming the token. That way given: void f g () { ... } typedef int I; we will stop after the body of the erroneously declared function, but before consuming the following `typedef' declaration. */ if (--nesting_depth == 0) { cp_lexer_consume_token (parser->lexer); return; } case CPP_OPEN_BRACE: ++nesting_depth; break; default: break; } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* This function is called at the end of a statement or declaration. If the next token is a semicolon, it is consumed; otherwise, error recovery is attempted. */ static void cp_parser_consume_semicolon_at_end_of_statement (cp_parser *parser) { /* Look for the trailing `;'. */ if (!cp_parser_require (parser, CPP_SEMICOLON, "`;'")) { /* If there is additional (erroneous) input, skip to the end of the statement. */ cp_parser_skip_to_end_of_statement (parser); /* If the next token is now a `;', consume it. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) cp_lexer_consume_token (parser->lexer); } } /* Skip tokens until we have consumed an entire block, or until we have consumed a non-nested `;'. */ static void cp_parser_skip_to_end_of_block_or_statement (cp_parser* parser) { int nesting_depth = 0; while (nesting_depth >= 0) { cp_token *token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_EOF: case CPP_PRAGMA_EOL: /* If we've run out of tokens, stop. */ return; case CPP_SEMICOLON: /* Stop if this is an unnested ';'. */ if (!nesting_depth) nesting_depth = -1; break; case CPP_CLOSE_BRACE: /* Stop if this is an unnested '}', or closes the outermost nesting level. */ nesting_depth--; if (!nesting_depth) nesting_depth = -1; break; case CPP_OPEN_BRACE: /* Nest. */ nesting_depth++; break; default: break; } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* Skip tokens until a non-nested closing curly brace is the next token, or there are no more tokens. Return true in the first case, false otherwise. */ static bool cp_parser_skip_to_closing_brace (cp_parser *parser) { unsigned nesting_depth = 0; while (true) { cp_token *token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_EOF: case CPP_PRAGMA_EOL: /* If we've run out of tokens, stop. */ return false; case CPP_CLOSE_BRACE: /* If the next token is a non-nested `}', then we have reached the end of the current block. */ if (nesting_depth-- == 0) return true; break; case CPP_OPEN_BRACE: /* If it the next token is a `{', then we are entering a new block. Consume the entire block. */ ++nesting_depth; break; default: break; } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } } /* Consume tokens until we reach the end of the pragma. The PRAGMA_TOK parameter is the PRAGMA token, allowing us to purge the entire pragma sequence. */ static void cp_parser_skip_to_pragma_eol (cp_parser* parser, cp_token *pragma_tok) { cp_token *token; parser->lexer->in_pragma = false; do token = cp_lexer_consume_token (parser->lexer); while (token->type != CPP_PRAGMA_EOL && token->type != CPP_EOF); /* Ensure that the pragma is not parsed again. */ cp_lexer_purge_tokens_after (parser->lexer, pragma_tok); } /* Require pragma end of line, resyncing with it as necessary. The arguments are as for cp_parser_skip_to_pragma_eol. */ static void cp_parser_require_pragma_eol (cp_parser *parser, cp_token *pragma_tok) { parser->lexer->in_pragma = false; if (!cp_parser_require (parser, CPP_PRAGMA_EOL, "end of line")) cp_parser_skip_to_pragma_eol (parser, pragma_tok); } /* This is a simple wrapper around make_typename_type. When the id is an unresolved identifier node, we can provide a superior diagnostic using cp_parser_diagnose_invalid_type_name. */ static tree cp_parser_make_typename_type (cp_parser *parser, tree scope, tree id) { tree result; if (TREE_CODE (id) == IDENTIFIER_NODE) { result = make_typename_type (scope, id, typename_type, /*complain=*/tf_none); if (result == error_mark_node) cp_parser_diagnose_invalid_type_name (parser, scope, id); return result; } return make_typename_type (scope, id, typename_type, tf_error); } /* This is a wrapper around the make_{pointer,ptrmem,reference}_declarator functions that decides which one to call based on the CODE and CLASS_TYPE arguments. The CODE argument should be one of the values returned by cp_parser_ptr_operator. */ static cp_declarator * cp_parser_make_indirect_declarator (enum tree_code code, tree class_type, cp_cv_quals cv_qualifiers, cp_declarator *target) { if (code == ERROR_MARK) return cp_error_declarator; if (code == INDIRECT_REF) if (class_type == NULL_TREE) return make_pointer_declarator (cv_qualifiers, target); else return make_ptrmem_declarator (cv_qualifiers, class_type, target); else if (code == ADDR_EXPR && class_type == NULL_TREE) return make_reference_declarator (cv_qualifiers, target, false); else if (code == NON_LVALUE_EXPR && class_type == NULL_TREE) return make_reference_declarator (cv_qualifiers, target, true); gcc_unreachable (); } /* Create a new C++ parser. */ static cp_parser * cp_parser_new (void) { cp_parser *parser; cp_lexer *lexer; unsigned i; /* cp_lexer_new_main is called before calling ggc_alloc because cp_lexer_new_main might load a PCH file. */ lexer = cp_lexer_new_main (); /* Initialize the binops_by_token so that we can get the tree directly from the token. */ for (i = 0; i < sizeof (binops) / sizeof (binops[0]); i++) binops_by_token[binops[i].token_type] = binops[i]; parser = GGC_CNEW (cp_parser); parser->lexer = lexer; parser->context = cp_parser_context_new (NULL); /* For now, we always accept GNU extensions. */ parser->allow_gnu_extensions_p = 1; /* The `>' token is a greater-than operator, not the end of a template-id. */ parser->greater_than_is_operator_p = true; parser->default_arg_ok_p = true; /* We are not parsing a constant-expression. */ parser->integral_constant_expression_p = false; parser->allow_non_integral_constant_expression_p = false; parser->non_integral_constant_expression_p = false; /* Local variable names are not forbidden. */ parser->local_variables_forbidden_p = false; /* We are not processing an `extern "C"' declaration. */ parser->in_unbraced_linkage_specification_p = false; /* We are not processing a declarator. */ parser->in_declarator_p = false; /* We are not processing a template-argument-list. */ parser->in_template_argument_list_p = false; /* We are not in an iteration statement. */ parser->in_statement = 0; /* We are not in a switch statement. */ parser->in_switch_statement_p = false; /* We are not parsing a type-id inside an expression. */ parser->in_type_id_in_expr_p = false; /* Declarations aren't implicitly extern "C". */ parser->implicit_extern_c = false; /* String literals should be translated to the execution character set. */ parser->translate_strings_p = true; /* We are not parsing a function body. */ parser->in_function_body = false; /* The unparsed function queue is empty. */ parser->unparsed_functions_queues = build_tree_list (NULL_TREE, NULL_TREE); /* There are no classes being defined. */ parser->num_classes_being_defined = 0; /* No template parameters apply. */ parser->num_template_parameter_lists = 0; return parser; } /* Create a cp_lexer structure which will emit the tokens in CACHE and push it onto the parser's lexer stack. This is used for delayed parsing of in-class method bodies and default arguments, and should not be confused with tentative parsing. */ static void cp_parser_push_lexer_for_tokens (cp_parser *parser, cp_token_cache *cache) { cp_lexer *lexer = cp_lexer_new_from_tokens (cache); lexer->next = parser->lexer; parser->lexer = lexer; /* Move the current source position to that of the first token in the new lexer. */ cp_lexer_set_source_position_from_token (lexer->next_token); } /* Pop the top lexer off the parser stack. This is never used for the "main" lexer, only for those pushed by cp_parser_push_lexer_for_tokens. */ static void cp_parser_pop_lexer (cp_parser *parser) { cp_lexer *lexer = parser->lexer; parser->lexer = lexer->next; cp_lexer_destroy (lexer); /* Put the current source position back where it was before this lexer was pushed. */ cp_lexer_set_source_position_from_token (parser->lexer->next_token); } /* Lexical conventions [gram.lex] */ /* Parse an identifier. Returns an IDENTIFIER_NODE representing the identifier. */ static tree cp_parser_identifier (cp_parser* parser) { cp_token *token; /* Look for the identifier. */ token = cp_parser_require (parser, CPP_NAME, "identifier"); /* Return the value. */ return token ? token->u.value : error_mark_node; } /* Parse a sequence of adjacent string constants. Returns a TREE_STRING representing the combined, nul-terminated string constant. If TRANSLATE is true, translate the string to the execution character set. If WIDE_OK is true, a wide string is invalid here. C++98 [lex.string] says that if a narrow string literal token is adjacent to a wide string literal token, the behavior is undefined. However, C99 6.4.5p4 says that this results in a wide string literal. We follow C99 here, for consistency with the C front end. This code is largely lifted from lex_string() in c-lex.c. FUTURE: ObjC++ will need to handle @-strings here. */ static tree cp_parser_string_literal (cp_parser *parser, bool translate, bool wide_ok) { tree value; bool wide = false; size_t count; struct obstack str_ob; cpp_string str, istr, *strs; cp_token *tok; tok = cp_lexer_peek_token (parser->lexer); if (!cp_parser_is_string_literal (tok)) { cp_parser_error (parser, "expected string-literal"); return error_mark_node; } /* Try to avoid the overhead of creating and destroying an obstack for the common case of just one string. */ if (!cp_parser_is_string_literal (cp_lexer_peek_nth_token (parser->lexer, 2))) { cp_lexer_consume_token (parser->lexer); str.text = (const unsigned char *)TREE_STRING_POINTER (tok->u.value); str.len = TREE_STRING_LENGTH (tok->u.value); count = 1; if (tok->type == CPP_WSTRING) wide = true; strs = &str; } else { gcc_obstack_init (&str_ob); count = 0; do { cp_lexer_consume_token (parser->lexer); count++; str.text = (const unsigned char *)TREE_STRING_POINTER (tok->u.value); str.len = TREE_STRING_LENGTH (tok->u.value); if (tok->type == CPP_WSTRING) wide = true; obstack_grow (&str_ob, &str, sizeof (cpp_string)); tok = cp_lexer_peek_token (parser->lexer); } while (cp_parser_is_string_literal (tok)); strs = (cpp_string *) obstack_finish (&str_ob); } if (wide && !wide_ok) { cp_parser_error (parser, "a wide string is invalid in this context"); wide = false; } if ((translate ? cpp_interpret_string : cpp_interpret_string_notranslate) (parse_in, strs, count, &istr, wide)) { value = build_string (istr.len, (const char *)istr.text); free (CONST_CAST (unsigned char *, istr.text)); TREE_TYPE (value) = wide ? wchar_array_type_node : char_array_type_node; value = fix_string_type (value); } else /* cpp_interpret_string has issued an error. */ value = error_mark_node; if (count > 1) obstack_free (&str_ob, 0); return value; } /* Basic concepts [gram.basic] */ /* Parse a translation-unit. translation-unit: declaration-seq [opt] Returns TRUE if all went well. */ static bool cp_parser_translation_unit (cp_parser* parser) { /* The address of the first non-permanent object on the declarator obstack. */ static void *declarator_obstack_base; bool success; /* Create the declarator obstack, if necessary. */ if (!cp_error_declarator) { gcc_obstack_init (&declarator_obstack); /* Create the error declarator. */ cp_error_declarator = make_declarator (cdk_error); /* Create the empty parameter list. */ no_parameters = make_parameter_declarator (NULL, NULL, NULL_TREE); /* Remember where the base of the declarator obstack lies. */ declarator_obstack_base = obstack_next_free (&declarator_obstack); } cp_parser_declaration_seq_opt (parser); /* If there are no tokens left then all went well. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EOF)) { /* Get rid of the token array; we don't need it any more. */ cp_lexer_destroy (parser->lexer); parser->lexer = NULL; /* This file might have been a context that's implicitly extern "C". If so, pop the lang context. (Only relevant for PCH.) */ if (parser->implicit_extern_c) { pop_lang_context (); parser->implicit_extern_c = false; } /* Finish up. */ finish_translation_unit (); success = true; } else { cp_parser_error (parser, "expected declaration"); success = false; } /* Make sure the declarator obstack was fully cleaned up. */ gcc_assert (obstack_next_free (&declarator_obstack) == declarator_obstack_base); /* All went well. */ return success; } /* Expressions [gram.expr] */ /* Parse a primary-expression. primary-expression: literal this ( expression ) id-expression GNU Extensions: primary-expression: ( compound-statement ) __builtin_va_arg ( assignment-expression , type-id ) __builtin_offsetof ( type-id , offsetof-expression ) C++ Extensions: __has_nothrow_assign ( type-id ) __has_nothrow_constructor ( type-id ) __has_nothrow_copy ( type-id ) __has_trivial_assign ( type-id ) __has_trivial_constructor ( type-id ) __has_trivial_copy ( type-id ) __has_trivial_destructor ( type-id ) __has_virtual_destructor ( type-id ) __is_abstract ( type-id ) __is_base_of ( type-id , type-id ) __is_class ( type-id ) __is_convertible_to ( type-id , type-id ) __is_empty ( type-id ) __is_enum ( type-id ) __is_pod ( type-id ) __is_polymorphic ( type-id ) __is_union ( type-id ) Objective-C++ Extension: primary-expression: objc-expression literal: __null ADDRESS_P is true iff this expression was immediately preceded by "&" and therefore might denote a pointer-to-member. CAST_P is true iff this expression is the target of a cast. TEMPLATE_ARG_P is true iff this expression is a template argument. Returns a representation of the expression. Upon return, *IDK indicates what kind of id-expression (if any) was present. */ static tree cp_parser_primary_expression (cp_parser *parser, bool address_p, bool cast_p, bool template_arg_p, cp_id_kind *idk) { cp_token *token; /* Assume the primary expression is not an id-expression. */ *idk = CP_ID_KIND_NONE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { /* literal: integer-literal character-literal floating-literal string-literal boolean-literal */ case CPP_CHAR: case CPP_WCHAR: case CPP_NUMBER: token = cp_lexer_consume_token (parser->lexer); /* Floating-point literals are only allowed in an integral constant expression if they are cast to an integral or enumeration type. */ if (TREE_CODE (token->u.value) == REAL_CST && parser->integral_constant_expression_p && pedantic) { /* CAST_P will be set even in invalid code like "int(2.7 + ...)". Therefore, we have to check that the next token is sure to end the cast. */ if (cast_p) { cp_token *next_token; next_token = cp_lexer_peek_token (parser->lexer); if (/* The comma at the end of an enumerator-definition. */ next_token->type != CPP_COMMA /* The curly brace at the end of an enum-specifier. */ && next_token->type != CPP_CLOSE_BRACE /* The end of a statement. */ && next_token->type != CPP_SEMICOLON /* The end of the cast-expression. */ && next_token->type != CPP_CLOSE_PAREN /* The end of an array bound. */ && next_token->type != CPP_CLOSE_SQUARE /* The closing ">" in a template-argument-list. */ && (next_token->type != CPP_GREATER || parser->greater_than_is_operator_p) /* C++0x only: A ">>" treated like two ">" tokens, in a template-argument-list. */ && (next_token->type != CPP_RSHIFT || (cxx_dialect == cxx98) || parser->greater_than_is_operator_p)) cast_p = false; } /* If we are within a cast, then the constraint that the cast is to an integral or enumeration type will be checked at that point. If we are not within a cast, then this code is invalid. */ if (!cast_p) cp_parser_non_integral_constant_expression (parser, "floating-point literal"); } return token->u.value; case CPP_STRING: case CPP_WSTRING: /* ??? Should wide strings be allowed when parser->translate_strings_p is false (i.e. in attributes)? If not, we can kill the third argument to cp_parser_string_literal. */ return cp_parser_string_literal (parser, parser->translate_strings_p, true); case CPP_OPEN_PAREN: { tree expr; bool saved_greater_than_is_operator_p; /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Within a parenthesized expression, a `>' token is always the greater-than operator. */ saved_greater_than_is_operator_p = parser->greater_than_is_operator_p; parser->greater_than_is_operator_p = true; /* If we see `( { ' then we are looking at the beginning of a GNU statement-expression. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) { /* Statement-expressions are not allowed by the standard. */ if (pedantic) pedwarn ("ISO C++ forbids braced-groups within expressions"); /* And they're not allowed outside of a function-body; you cannot, for example, write: int i = ({ int j = 3; j + 1; }); at class or namespace scope. */ if (!parser->in_function_body || parser->in_template_argument_list_p) { error ("statement-expressions are not allowed outside " "functions nor in template-argument lists"); cp_parser_skip_to_end_of_block_or_statement (parser); expr = error_mark_node; } else { /* Start the statement-expression. */ expr = begin_stmt_expr (); /* Parse the compound-statement. */ cp_parser_compound_statement (parser, expr, false); /* Finish up. */ expr = finish_stmt_expr (expr, false); } } else { /* Parse the parenthesized expression. */ expr = cp_parser_expression (parser, cast_p); /* Let the front end know that this expression was enclosed in parentheses. This matters in case, for example, the expression is of the form `A::B', since `&A::B' might be a pointer-to-member, but `&(A::B)' is not. */ finish_parenthesized_expr (expr); } /* The `>' token might be the end of a template-id or template-parameter-list now. */ parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; /* Consume the `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_end_of_statement (parser); return expr; } case CPP_KEYWORD: switch (token->keyword) { /* These two are the boolean literals. */ case RID_TRUE: cp_lexer_consume_token (parser->lexer); return boolean_true_node; case RID_FALSE: cp_lexer_consume_token (parser->lexer); return boolean_false_node; /* The `__null' literal. */ case RID_NULL: cp_lexer_consume_token (parser->lexer); return null_node; /* Recognize the `this' keyword. */ case RID_THIS: cp_lexer_consume_token (parser->lexer); if (parser->local_variables_forbidden_p) { error ("% may not be used in this context"); return error_mark_node; } /* Pointers cannot appear in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "`this'")) return error_mark_node; return finish_this_expr (); /* The `operator' keyword can be the beginning of an id-expression. */ case RID_OPERATOR: goto id_expression; case RID_FUNCTION_NAME: case RID_PRETTY_FUNCTION_NAME: case RID_C99_FUNCTION_NAME: /* The symbols __FUNCTION__, __PRETTY_FUNCTION__, and __func__ are the names of variables -- but they are treated specially. Therefore, they are handled here, rather than relying on the generic id-expression logic below. Grammatically, these names are id-expressions. Consume the token. */ token = cp_lexer_consume_token (parser->lexer); /* Look up the name. */ return finish_fname (token->u.value); case RID_VA_ARG: { tree expression; tree type; /* The `__builtin_va_arg' construct is used to handle `va_arg'. Consume the `__builtin_va_arg' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the opening `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Now, parse the assignment-expression. */ expression = cp_parser_assignment_expression (parser, /*cast_p=*/false); /* Look for the `,'. */ cp_parser_require (parser, CPP_COMMA, "`,'"); /* Parse the type-id. */ type = cp_parser_type_id (parser); /* Look for the closing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Using `va_arg' in a constant-expression is not allowed. */ if (cp_parser_non_integral_constant_expression (parser, "`va_arg'")) return error_mark_node; return build_x_va_arg (expression, type); } case RID_OFFSETOF: return cp_parser_builtin_offsetof (parser); case RID_HAS_NOTHROW_ASSIGN: case RID_HAS_NOTHROW_CONSTRUCTOR: case RID_HAS_NOTHROW_COPY: case RID_HAS_TRIVIAL_ASSIGN: case RID_HAS_TRIVIAL_CONSTRUCTOR: case RID_HAS_TRIVIAL_COPY: case RID_HAS_TRIVIAL_DESTRUCTOR: case RID_HAS_VIRTUAL_DESTRUCTOR: case RID_IS_ABSTRACT: case RID_IS_BASE_OF: case RID_IS_CLASS: case RID_IS_CONVERTIBLE_TO: case RID_IS_EMPTY: case RID_IS_ENUM: case RID_IS_POD: case RID_IS_POLYMORPHIC: case RID_IS_UNION: return cp_parser_trait_expr (parser, token->keyword); /* Objective-C++ expressions. */ case RID_AT_ENCODE: case RID_AT_PROTOCOL: case RID_AT_SELECTOR: return cp_parser_objc_expression (parser); default: cp_parser_error (parser, "expected primary-expression"); return error_mark_node; } /* An id-expression can start with either an identifier, a `::' as the beginning of a qualified-id, or the "operator" keyword. */ case CPP_NAME: case CPP_SCOPE: case CPP_TEMPLATE_ID: case CPP_NESTED_NAME_SPECIFIER: { tree id_expression; tree decl; const char *error_msg; bool template_p; bool done; id_expression: /* Parse the id-expression. */ id_expression = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, &template_p, /*declarator_p=*/false, /*optional_p=*/false); if (id_expression == error_mark_node) return error_mark_node; token = cp_lexer_peek_token (parser->lexer); done = (token->type != CPP_OPEN_SQUARE && token->type != CPP_OPEN_PAREN && token->type != CPP_DOT && token->type != CPP_DEREF && token->type != CPP_PLUS_PLUS && token->type != CPP_MINUS_MINUS); /* If we have a template-id, then no further lookup is required. If the template-id was for a template-class, we will sometimes have a TYPE_DECL at this point. */ if (TREE_CODE (id_expression) == TEMPLATE_ID_EXPR || TREE_CODE (id_expression) == TYPE_DECL) decl = id_expression; /* Look up the name. */ else { tree ambiguous_decls; decl = cp_parser_lookup_name (parser, id_expression, none_type, template_p, /*is_namespace=*/false, /*check_dependency=*/true, &ambiguous_decls); /* If the lookup was ambiguous, an error will already have been issued. */ if (ambiguous_decls) return error_mark_node; /* In Objective-C++, an instance variable (ivar) may be preferred to whatever cp_parser_lookup_name() found. */ decl = objc_lookup_ivar (decl, id_expression); /* If name lookup gives us a SCOPE_REF, then the qualifying scope was dependent. */ if (TREE_CODE (decl) == SCOPE_REF) { /* At this point, we do not know if DECL is a valid integral constant expression. We assume that it is in fact such an expression, so that code like: template struct A { int a[B::i]; }; is accepted. At template-instantiation time, we will check that B::i is actually a constant. */ return decl; } /* Check to see if DECL is a local variable in a context where that is forbidden. */ if (parser->local_variables_forbidden_p && local_variable_p (decl)) { /* It might be that we only found DECL because we are trying to be generous with pre-ISO scoping rules. For example, consider: int i; void g() { for (int i = 0; i < 10; ++i) {} extern void f(int j = i); } Here, name look up will originally find the out of scope `i'. We need to issue a warning message, but then use the global `i'. */ decl = check_for_out_of_scope_variable (decl); if (local_variable_p (decl)) { error ("local variable %qD may not appear in this context", decl); return error_mark_node; } } } decl = (finish_id_expression (id_expression, decl, parser->scope, idk, parser->integral_constant_expression_p, parser->allow_non_integral_constant_expression_p, &parser->non_integral_constant_expression_p, template_p, done, address_p, template_arg_p, &error_msg)); if (error_msg) cp_parser_error (parser, error_msg); return decl; } /* Anything else is an error. */ default: /* ...unless we have an Objective-C++ message or string literal, that is. */ if (c_dialect_objc () && (token->type == CPP_OPEN_SQUARE || token->type == CPP_OBJC_STRING)) return cp_parser_objc_expression (parser); cp_parser_error (parser, "expected primary-expression"); return error_mark_node; } } /* Parse an id-expression. id-expression: unqualified-id qualified-id qualified-id: :: [opt] nested-name-specifier template [opt] unqualified-id :: identifier :: operator-function-id :: template-id Return a representation of the unqualified portion of the identifier. Sets PARSER->SCOPE to the qualifying scope if there is a `::' or nested-name-specifier. Often, if the id-expression was a qualified-id, the caller will want to make a SCOPE_REF to represent the qualified-id. This function does not do this in order to avoid wastefully creating SCOPE_REFs when they are not required. If TEMPLATE_KEYWORD_P is true, then we have just seen the `template' keyword. If CHECK_DEPENDENCY_P is false, then names are looked up inside uninstantiated templates. If *TEMPLATE_P is non-NULL, it is set to true iff the `template' keyword is used to explicitly indicate that the entity named is a template. If DECLARATOR_P is true, the id-expression is appearing as part of a declarator, rather than as part of an expression. */ static tree cp_parser_id_expression (cp_parser *parser, bool template_keyword_p, bool check_dependency_p, bool *template_p, bool declarator_p, bool optional_p) { bool global_scope_p; bool nested_name_specifier_p; /* Assume the `template' keyword was not used. */ if (template_p) *template_p = template_keyword_p; /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the optional nested-name-specifier. */ nested_name_specifier_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, check_dependency_p, /*type_p=*/false, declarator_p) != NULL_TREE); /* If there is a nested-name-specifier, then we are looking at the first qualified-id production. */ if (nested_name_specifier_p) { tree saved_scope; tree saved_object_scope; tree saved_qualifying_scope; tree unqualified_id; bool is_template; /* See if the next token is the `template' keyword. */ if (!template_p) template_p = &is_template; *template_p = cp_parser_optional_template_keyword (parser); /* Name lookup we do during the processing of the unqualified-id might obliterate SCOPE. */ saved_scope = parser->scope; saved_object_scope = parser->object_scope; saved_qualifying_scope = parser->qualifying_scope; /* Process the final unqualified-id. */ unqualified_id = cp_parser_unqualified_id (parser, *template_p, check_dependency_p, declarator_p, /*optional_p=*/false); /* Restore the SAVED_SCOPE for our caller. */ parser->scope = saved_scope; parser->object_scope = saved_object_scope; parser->qualifying_scope = saved_qualifying_scope; return unqualified_id; } /* Otherwise, if we are in global scope, then we are looking at one of the other qualified-id productions. */ else if (global_scope_p) { cp_token *token; tree id; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's an identifier, and the next token is not a "<", then we can avoid the template-id case. This is an optimization for this common case. */ if (token->type == CPP_NAME && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2)) return cp_parser_identifier (parser); cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, declarator_p); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* Peek at the next token. (Changes in the token buffer may have invalidated the pointer obtained above.) */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_NAME: return cp_parser_identifier (parser); case CPP_KEYWORD: if (token->keyword == RID_OPERATOR) return cp_parser_operator_function_id (parser); /* Fall through. */ default: cp_parser_error (parser, "expected id-expression"); return error_mark_node; } } else return cp_parser_unqualified_id (parser, template_keyword_p, /*check_dependency_p=*/true, declarator_p, optional_p); } /* Parse an unqualified-id. unqualified-id: identifier operator-function-id conversion-function-id ~ class-name template-id If TEMPLATE_KEYWORD_P is TRUE, we have just seen the `template' keyword, in a construct like `A::template ...'. Returns a representation of unqualified-id. For the `identifier' production, an IDENTIFIER_NODE is returned. For the `~ class-name' production a BIT_NOT_EXPR is returned; the operand of the BIT_NOT_EXPR is an IDENTIFIER_NODE for the class-name. For the other productions, see the documentation accompanying the corresponding parsing functions. If CHECK_DEPENDENCY_P is false, names are looked up in uninstantiated templates. If DECLARATOR_P is true, the unqualified-id is appearing as part of a declarator, rather than as part of an expression. */ static tree cp_parser_unqualified_id (cp_parser* parser, bool template_keyword_p, bool check_dependency_p, bool declarator_p, bool optional_p) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_NAME: { tree id; /* We don't know yet whether or not this will be a template-id. */ cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, template_keyword_p, check_dependency_p, declarator_p); /* If it worked, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* Otherwise, it's an ordinary identifier. */ return cp_parser_identifier (parser); } case CPP_TEMPLATE_ID: return cp_parser_template_id (parser, template_keyword_p, check_dependency_p, declarator_p); case CPP_COMPL: { tree type_decl; tree qualifying_scope; tree object_scope; tree scope; bool done; /* Consume the `~' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the class-name. The standard, as written, seems to say that: template struct S { ~S (); }; template S::~S() {} is invalid, since `~' must be followed by a class-name, but `S' is dependent, and so not known to be a class. That's not right; we need to look in uninstantiated templates. A further complication arises from: template void f(T t) { t.T::~T(); } Here, it is not possible to look up `T' in the scope of `T' itself. We must look in both the current scope, and the scope of the containing complete expression. Yet another issue is: struct S { int S; ~S(); }; S::~S() {} The standard does not seem to say that the `S' in `~S' should refer to the type `S' and not the data member `S::S'. */ /* DR 244 says that we look up the name after the "~" in the same scope as we looked up the qualifying name. That idea isn't fully worked out; it's more complicated than that. */ scope = parser->scope; object_scope = parser->object_scope; qualifying_scope = parser->qualifying_scope; /* Check for invalid scopes. */ if (scope == error_mark_node) { if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) cp_lexer_consume_token (parser->lexer); return error_mark_node; } if (scope && TREE_CODE (scope) == NAMESPACE_DECL) { if (!cp_parser_uncommitted_to_tentative_parse_p (parser)) error ("scope %qT before %<~%> is not a class-name", scope); cp_parser_simulate_error (parser); if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) cp_lexer_consume_token (parser->lexer); return error_mark_node; } gcc_assert (!scope || TYPE_P (scope)); /* If the name is of the form "X::~X" it's OK. */ token = cp_lexer_peek_token (parser->lexer); if (scope && token->type == CPP_NAME && (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_OPEN_PAREN) && constructor_name_p (token->u.value, scope)) { cp_lexer_consume_token (parser->lexer); return build_nt (BIT_NOT_EXPR, scope); } /* If there was an explicit qualification (S::~T), first look in the scope given by the qualification (i.e., S). */ done = false; type_decl = NULL_TREE; if (scope) { cp_parser_parse_tentatively (parser); type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, none_type, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); if (cp_parser_parse_definitely (parser)) done = true; } /* In "N::S::~S", look in "N" as well. */ if (!done && scope && qualifying_scope) { cp_parser_parse_tentatively (parser); parser->scope = qualifying_scope; parser->object_scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, none_type, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); if (cp_parser_parse_definitely (parser)) done = true; } /* In "p->S::~T", look in the scope given by "*p" as well. */ else if (!done && object_scope) { cp_parser_parse_tentatively (parser); parser->scope = object_scope; parser->object_scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, none_type, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); if (cp_parser_parse_definitely (parser)) done = true; } /* Look in the surrounding context. */ if (!done) { parser->scope = NULL_TREE; parser->object_scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, none_type, /*check_dependency=*/false, /*class_head_p=*/false, declarator_p); } /* If an error occurred, assume that the name of the destructor is the same as the name of the qualifying class. That allows us to keep parsing after running into ill-formed destructor names. */ if (type_decl == error_mark_node && scope) return build_nt (BIT_NOT_EXPR, scope); else if (type_decl == error_mark_node) return error_mark_node; /* Check that destructor name and scope match. */ if (declarator_p && scope && !check_dtor_name (scope, type_decl)) { if (!cp_parser_uncommitted_to_tentative_parse_p (parser)) error ("declaration of %<~%T%> as member of %qT", type_decl, scope); cp_parser_simulate_error (parser); return error_mark_node; } /* [class.dtor] A typedef-name that names a class shall not be used as the identifier in the declarator for a destructor declaration. */ if (declarator_p && !DECL_IMPLICIT_TYPEDEF_P (type_decl) && !DECL_SELF_REFERENCE_P (type_decl) && !cp_parser_uncommitted_to_tentative_parse_p (parser)) error ("typedef-name %qD used as destructor declarator", type_decl); return build_nt (BIT_NOT_EXPR, TREE_TYPE (type_decl)); } case CPP_KEYWORD: if (token->keyword == RID_OPERATOR) { tree id; /* This could be a template-id, so we try that first. */ cp_parser_parse_tentatively (parser); /* Try a template-id. */ id = cp_parser_template_id (parser, template_keyword_p, /*check_dependency_p=*/true, declarator_p); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* We still don't know whether we're looking at an operator-function-id or a conversion-function-id. */ cp_parser_parse_tentatively (parser); /* Try an operator-function-id. */ id = cp_parser_operator_function_id (parser); /* If that didn't work, try a conversion-function-id. */ if (!cp_parser_parse_definitely (parser)) id = cp_parser_conversion_function_id (parser); return id; } /* Fall through. */ default: if (optional_p) return NULL_TREE; cp_parser_error (parser, "expected unqualified-id"); return error_mark_node; } } /* Parse an (optional) nested-name-specifier. nested-name-specifier: class-or-namespace-name :: nested-name-specifier [opt] class-or-namespace-name :: template nested-name-specifier [opt] PARSER->SCOPE should be set appropriately before this function is called. TYPENAME_KEYWORD_P is TRUE if the `typename' keyword is in effect. TYPE_P is TRUE if we non-type bindings should be ignored in name lookups. Sets PARSER->SCOPE to the class (TYPE) or namespace (NAMESPACE_DECL) specified by the nested-name-specifier, or leaves it unchanged if there is no nested-name-specifier. Returns the new scope iff there is a nested-name-specifier, or NULL_TREE otherwise. If IS_DECLARATION is TRUE, the nested-name-specifier is known to be part of a declaration and/or decl-specifier. */ static tree cp_parser_nested_name_specifier_opt (cp_parser *parser, bool typename_keyword_p, bool check_dependency_p, bool type_p, bool is_declaration) { bool success = false; cp_token_position start = 0; cp_token *token; /* Remember where the nested-name-specifier starts. */ if (cp_parser_uncommitted_to_tentative_parse_p (parser)) { start = cp_lexer_token_position (parser->lexer, false); push_deferring_access_checks (dk_deferred); } while (true) { tree new_scope; tree old_scope; tree saved_qualifying_scope; bool template_keyword_p; /* Spot cases that cannot be the beginning of a nested-name-specifier. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is CPP_NESTED_NAME_SPECIFIER, just process the already parsed nested-name-specifier. */ if (token->type == CPP_NESTED_NAME_SPECIFIER) { /* Grab the nested-name-specifier and continue the loop. */ cp_parser_pre_parsed_nested_name_specifier (parser); /* If we originally encountered this nested-name-specifier with IS_DECLARATION set to false, we will not have resolved TYPENAME_TYPEs, so we must do so here. */ if (is_declaration && TREE_CODE (parser->scope) == TYPENAME_TYPE) { new_scope = resolve_typename_type (parser->scope, /*only_current_p=*/false); if (TREE_CODE (new_scope) != TYPENAME_TYPE) parser->scope = new_scope; } success = true; continue; } /* Spot cases that cannot be the beginning of a nested-name-specifier. On the second and subsequent times through the loop, we look for the `template' keyword. */ if (success && token->keyword == RID_TEMPLATE) ; /* A template-id can start a nested-name-specifier. */ else if (token->type == CPP_TEMPLATE_ID) ; else { /* If the next token is not an identifier, then it is definitely not a class-or-namespace-name. */ if (token->type != CPP_NAME) break; /* If the following token is neither a `<' (to begin a template-id), nor a `::', then we are not looking at a nested-name-specifier. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); if (token->type != CPP_SCOPE && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2)) break; } /* The nested-name-specifier is optional, so we parse tentatively. */ cp_parser_parse_tentatively (parser); /* Look for the optional `template' keyword, if this isn't the first time through the loop. */ if (success) template_keyword_p = cp_parser_optional_template_keyword (parser); else template_keyword_p = false; /* Save the old scope since the name lookup we are about to do might destroy it. */ old_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; /* In a declarator-id like "X::I::Y" we must be able to look up names in "X::I" in order to determine that "Y" is a template. So, if we have a typename at this point, we make an effort to look through it. */ if (is_declaration && !typename_keyword_p && parser->scope && TREE_CODE (parser->scope) == TYPENAME_TYPE) parser->scope = resolve_typename_type (parser->scope, /*only_current_p=*/false); /* Parse the qualifying entity. */ new_scope = cp_parser_class_or_namespace_name (parser, typename_keyword_p, template_keyword_p, check_dependency_p, type_p, is_declaration); /* Look for the `::' token. */ cp_parser_require (parser, CPP_SCOPE, "`::'"); /* If we found what we wanted, we keep going; otherwise, we're done. */ if (!cp_parser_parse_definitely (parser)) { bool error_p = false; /* Restore the OLD_SCOPE since it was valid before the failed attempt at finding the last class-or-namespace-name. */ parser->scope = old_scope; parser->qualifying_scope = saved_qualifying_scope; if (cp_parser_uncommitted_to_tentative_parse_p (parser)) break; /* If the next token is an identifier, and the one after that is a `::', then any valid interpretation would have found a class-or-namespace-name. */ while (cp_lexer_next_token_is (parser->lexer, CPP_NAME) && (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_SCOPE) && (cp_lexer_peek_nth_token (parser->lexer, 3)->type != CPP_COMPL)) { token = cp_lexer_consume_token (parser->lexer); if (!error_p) { if (!token->ambiguous_p) { tree decl; tree ambiguous_decls; decl = cp_parser_lookup_name (parser, token->u.value, none_type, /*is_template=*/false, /*is_namespace=*/false, /*check_dependency=*/true, &ambiguous_decls); if (TREE_CODE (decl) == TEMPLATE_DECL) error ("%qD used without template parameters", decl); else if (ambiguous_decls) { error ("reference to %qD is ambiguous", token->u.value); print_candidates (ambiguous_decls); decl = error_mark_node; } else cp_parser_name_lookup_error (parser, token->u.value, decl, "is not a class or namespace"); } parser->scope = error_mark_node; error_p = true; /* Treat this as a successful nested-name-specifier due to: [basic.lookup.qual] If the name found is not a class-name (clause _class_) or namespace-name (_namespace.def_), the program is ill-formed. */ success = true; } cp_lexer_consume_token (parser->lexer); } break; } /* We've found one valid nested-name-specifier. */ success = true; /* Name lookup always gives us a DECL. */ if (TREE_CODE (new_scope) == TYPE_DECL) new_scope = TREE_TYPE (new_scope); /* Uses of "template" must be followed by actual templates. */ if (template_keyword_p && !(CLASS_TYPE_P (new_scope) && ((CLASSTYPE_USE_TEMPLATE (new_scope) && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (new_scope))) || CLASSTYPE_IS_TEMPLATE (new_scope))) && !(TREE_CODE (new_scope) == TYPENAME_TYPE && (TREE_CODE (TYPENAME_TYPE_FULLNAME (new_scope)) == TEMPLATE_ID_EXPR))) pedwarn (TYPE_P (new_scope) ? "%qT is not a template" : "%qD is not a template", new_scope); /* If it is a class scope, try to complete it; we are about to be looking up names inside the class. */ if (TYPE_P (new_scope) /* Since checking types for dependency can be expensive, avoid doing it if the type is already complete. */ && !COMPLETE_TYPE_P (new_scope) /* Do not try to complete dependent types. */ && !dependent_type_p (new_scope)) { new_scope = complete_type (new_scope); /* If it is a typedef to current class, use the current class instead, as the typedef won't have any names inside it yet. */ if (!COMPLETE_TYPE_P (new_scope) && currently_open_class (new_scope)) new_scope = TYPE_MAIN_VARIANT (new_scope); } /* Make sure we look in the right scope the next time through the loop. */ parser->scope = new_scope; } /* If parsing tentatively, replace the sequence of tokens that makes up the nested-name-specifier with a CPP_NESTED_NAME_SPECIFIER token. That way, should we re-parse the token stream, we will not have to repeat the effort required to do the parse, nor will we issue duplicate error messages. */ if (success && start) { cp_token *token; token = cp_lexer_token_at (parser->lexer, start); /* Reset the contents of the START token. */ token->type = CPP_NESTED_NAME_SPECIFIER; /* Retrieve any deferred checks. Do not pop this access checks yet so the memory will not be reclaimed during token replacing below. */ token->u.tree_check_value = GGC_CNEW (struct tree_check); token->u.tree_check_value->value = parser->scope; token->u.tree_check_value->checks = get_deferred_access_checks (); token->u.tree_check_value->qualifying_scope = parser->qualifying_scope; token->keyword = RID_MAX; /* Purge all subsequent tokens. */ cp_lexer_purge_tokens_after (parser->lexer, start); } if (start) pop_to_parent_deferring_access_checks (); return success ? parser->scope : NULL_TREE; } /* Parse a nested-name-specifier. See cp_parser_nested_name_specifier_opt for details. This function behaves identically, except that it will an issue an error if no nested-name-specifier is present. */ static tree cp_parser_nested_name_specifier (cp_parser *parser, bool typename_keyword_p, bool check_dependency_p, bool type_p, bool is_declaration) { tree scope; /* Look for the nested-name-specifier. */ scope = cp_parser_nested_name_specifier_opt (parser, typename_keyword_p, check_dependency_p, type_p, is_declaration); /* If it was not present, issue an error message. */ if (!scope) { cp_parser_error (parser, "expected nested-name-specifier"); parser->scope = NULL_TREE; } return scope; } /* Parse a class-or-namespace-name. class-or-namespace-name: class-name namespace-name TYPENAME_KEYWORD_P is TRUE iff the `typename' keyword is in effect. TEMPLATE_KEYWORD_P is TRUE iff the `template' keyword is in effect. CHECK_DEPENDENCY_P is FALSE iff dependent names should be looked up. TYPE_P is TRUE iff the next name should be taken as a class-name, even the same name is declared to be another entity in the same scope. Returns the class (TYPE_DECL) or namespace (NAMESPACE_DECL) specified by the class-or-namespace-name. If neither is found the ERROR_MARK_NODE is returned. */ static tree cp_parser_class_or_namespace_name (cp_parser *parser, bool typename_keyword_p, bool template_keyword_p, bool check_dependency_p, bool type_p, bool is_declaration) { tree saved_scope; tree saved_qualifying_scope; tree saved_object_scope; tree scope; bool only_class_p; /* Before we try to parse the class-name, we must save away the current PARSER->SCOPE since cp_parser_class_name will destroy it. */ saved_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; saved_object_scope = parser->object_scope; /* Try for a class-name first. If the SAVED_SCOPE is a type, then there is no need to look for a namespace-name. */ only_class_p = template_keyword_p || (saved_scope && TYPE_P (saved_scope)); if (!only_class_p) cp_parser_parse_tentatively (parser); scope = cp_parser_class_name (parser, typename_keyword_p, template_keyword_p, type_p ? class_type : none_type, check_dependency_p, /*class_head_p=*/false, is_declaration); /* If that didn't work, try for a namespace-name. */ if (!only_class_p && !cp_parser_parse_definitely (parser)) { /* Restore the saved scope. */ parser->scope = saved_scope; parser->qualifying_scope = saved_qualifying_scope; parser->object_scope = saved_object_scope; /* If we are not looking at an identifier followed by the scope resolution operator, then this is not part of a nested-name-specifier. (Note that this function is only used to parse the components of a nested-name-specifier.) */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_NAME) || cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE) return error_mark_node; scope = cp_parser_namespace_name (parser); } return scope; } /* Parse a postfix-expression. postfix-expression: primary-expression postfix-expression [ expression ] postfix-expression ( expression-list [opt] ) simple-type-specifier ( expression-list [opt] ) typename :: [opt] nested-name-specifier identifier ( expression-list [opt] ) typename :: [opt] nested-name-specifier template [opt] template-id ( expression-list [opt] ) postfix-expression . template [opt] id-expression postfix-expression -> template [opt] id-expression postfix-expression . pseudo-destructor-name postfix-expression -> pseudo-destructor-name postfix-expression ++ postfix-expression -- dynamic_cast < type-id > ( expression ) static_cast < type-id > ( expression ) reinterpret_cast < type-id > ( expression ) const_cast < type-id > ( expression ) typeid ( expression ) typeid ( type-id ) GNU Extension: postfix-expression: ( type-id ) { initializer-list , [opt] } This extension is a GNU version of the C99 compound-literal construct. (The C99 grammar uses `type-name' instead of `type-id', but they are essentially the same concept.) If ADDRESS_P is true, the postfix expression is the operand of the `&' operator. CAST_P is true if this expression is the target of a cast. If MEMBER_ACCESS_ONLY_P, we only allow postfix expressions that are class member access expressions [expr.ref]. Returns a representation of the expression. */ static tree cp_parser_postfix_expression (cp_parser *parser, bool address_p, bool cast_p, bool member_access_only_p) { cp_token *token; enum rid keyword; cp_id_kind idk = CP_ID_KIND_NONE; tree postfix_expression = NULL_TREE; bool is_member_access = false; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Some of the productions are determined by keywords. */ keyword = token->keyword; switch (keyword) { case RID_DYNCAST: case RID_STATCAST: case RID_REINTCAST: case RID_CONSTCAST: { tree type; tree expression; const char *saved_message; /* All of these can be handled in the same way from the point of view of parsing. Begin by consuming the token identifying the cast. */ cp_lexer_consume_token (parser->lexer); /* New types cannot be defined in the cast. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in casts"; /* Look for the opening `<'. */ cp_parser_require (parser, CPP_LESS, "`<'"); /* Parse the type to which we are casting. */ type = cp_parser_type_id (parser); /* Look for the closing `>'. */ cp_parser_require (parser, CPP_GREATER, "`>'"); /* Restore the old message. */ parser->type_definition_forbidden_message = saved_message; /* And the expression which is being cast. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); expression = cp_parser_expression (parser, /*cast_p=*/true); cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Only type conversions to integral or enumeration types can be used in constant-expressions. */ if (!cast_valid_in_integral_constant_expression_p (type) && (cp_parser_non_integral_constant_expression (parser, "a cast to a type other than an integral or " "enumeration type"))) return error_mark_node; switch (keyword) { case RID_DYNCAST: postfix_expression = build_dynamic_cast (type, expression, tf_warning_or_error); break; case RID_STATCAST: postfix_expression = build_static_cast (type, expression, tf_warning_or_error); break; case RID_REINTCAST: postfix_expression = build_reinterpret_cast (type, expression, tf_warning_or_error); break; case RID_CONSTCAST: postfix_expression = build_const_cast (type, expression, tf_warning_or_error); break; default: gcc_unreachable (); } } break; case RID_TYPEID: { tree type; const char *saved_message; bool saved_in_type_id_in_expr_p; /* Consume the `typeid' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `(' token. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Types cannot be defined in a `typeid' expression. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in a `typeid\' expression"; /* We can't be sure yet whether we're looking at a type-id or an expression. */ cp_parser_parse_tentatively (parser); /* Try a type-id first. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; type = cp_parser_type_id (parser); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; /* Look for the `)' token. Otherwise, we can't be sure that we're not looking at an expression: consider `typeid (int (3))', for example. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* If all went well, simply lookup the type-id. */ if (cp_parser_parse_definitely (parser)) postfix_expression = get_typeid (type); /* Otherwise, fall back to the expression variant. */ else { tree expression; /* Look for an expression. */ expression = cp_parser_expression (parser, /*cast_p=*/false); /* Compute its typeid. */ postfix_expression = build_typeid (expression); /* Look for the `)' token. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); } /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; /* `typeid' may not appear in an integral constant expression. */ if (cp_parser_non_integral_constant_expression(parser, "`typeid' operator")) return error_mark_node; } break; case RID_TYPENAME: { tree type; /* The syntax permitted here is the same permitted for an elaborated-type-specifier. */ type = cp_parser_elaborated_type_specifier (parser, /*is_friend=*/false, /*is_declaration=*/false); postfix_expression = cp_parser_functional_cast (parser, type); } break; default: { tree type; /* If the next thing is a simple-type-specifier, we may be looking at a functional cast. We could also be looking at an id-expression. So, we try the functional cast, and if that doesn't work we fall back to the primary-expression. */ cp_parser_parse_tentatively (parser); /* Look for the simple-type-specifier. */ type = cp_parser_simple_type_specifier (parser, /*decl_specs=*/NULL, CP_PARSER_FLAGS_NONE); /* Parse the cast itself. */ if (!cp_parser_error_occurred (parser)) postfix_expression = cp_parser_functional_cast (parser, type); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) break; /* If the functional-cast didn't work out, try a compound-literal. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { VEC(constructor_elt,gc) *initializer_list = NULL; bool saved_in_type_id_in_expr_p; cp_parser_parse_tentatively (parser); /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the type. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; type = cp_parser_type_id (parser); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Look for the `{'. */ cp_parser_require (parser, CPP_OPEN_BRACE, "`{'"); /* If things aren't going well, there's no need to keep going. */ if (!cp_parser_error_occurred (parser)) { bool non_constant_p; /* Parse the initializer-list. */ initializer_list = cp_parser_initializer_list (parser, &non_constant_p); /* Allow a trailing `,'. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) cp_lexer_consume_token (parser->lexer); /* Look for the final `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } /* If that worked, we're definitely looking at a compound-literal expression. */ if (cp_parser_parse_definitely (parser)) { /* Warn the user that a compound literal is not allowed in standard C++. */ if (pedantic) pedwarn ("ISO C++ forbids compound-literals"); /* For simplicity, we disallow compound literals in constant-expressions. We could allow compound literals of integer type, whose initializer was a constant, in constant expressions. Permitting that usage, as a further extension, would not change the meaning of any currently accepted programs. (Of course, as compound literals are not part of ISO C++, the standard has nothing to say.) */ if (cp_parser_non_integral_constant_expression (parser, "non-constant compound literals")) { postfix_expression = error_mark_node; break; } /* Form the representation of the compound-literal. */ postfix_expression = finish_compound_literal (type, initializer_list); break; } } /* It must be a primary-expression. */ postfix_expression = cp_parser_primary_expression (parser, address_p, cast_p, /*template_arg_p=*/false, &idk); } break; } /* Keep looping until the postfix-expression is complete. */ while (true) { if (idk == CP_ID_KIND_UNQUALIFIED && TREE_CODE (postfix_expression) == IDENTIFIER_NODE && cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_PAREN)) /* It is not a Koenig lookup function call. */ postfix_expression = unqualified_name_lookup_error (postfix_expression); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_OPEN_SQUARE: postfix_expression = cp_parser_postfix_open_square_expression (parser, postfix_expression, false); idk = CP_ID_KIND_NONE; is_member_access = false; break; case CPP_OPEN_PAREN: /* postfix-expression ( expression-list [opt] ) */ { bool koenig_p; bool is_builtin_constant_p; bool saved_integral_constant_expression_p = false; bool saved_non_integral_constant_expression_p = false; tree args; is_member_access = false; is_builtin_constant_p = DECL_IS_BUILTIN_CONSTANT_P (postfix_expression); if (is_builtin_constant_p) { /* The whole point of __builtin_constant_p is to allow non-constant expressions to appear as arguments. */ saved_integral_constant_expression_p = parser->integral_constant_expression_p; saved_non_integral_constant_expression_p = parser->non_integral_constant_expression_p; parser->integral_constant_expression_p = false; } args = (cp_parser_parenthesized_expression_list (parser, /*is_attribute_list=*/false, /*cast_p=*/false, /*allow_expansion_p=*/true, /*non_constant_p=*/NULL)); if (is_builtin_constant_p) { parser->integral_constant_expression_p = saved_integral_constant_expression_p; parser->non_integral_constant_expression_p = saved_non_integral_constant_expression_p; } if (args == error_mark_node) { postfix_expression = error_mark_node; break; } /* Function calls are not permitted in constant-expressions. */ if (! builtin_valid_in_constant_expr_p (postfix_expression) && cp_parser_non_integral_constant_expression (parser, "a function call")) { postfix_expression = error_mark_node; break; } koenig_p = false; if (idk == CP_ID_KIND_UNQUALIFIED) { if (TREE_CODE (postfix_expression) == IDENTIFIER_NODE) { if (args) { koenig_p = true; postfix_expression = perform_koenig_lookup (postfix_expression, args); } else postfix_expression = unqualified_fn_lookup_error (postfix_expression); } /* We do not perform argument-dependent lookup if normal lookup finds a non-function, in accordance with the expected resolution of DR 218. */ else if (args && is_overloaded_fn (postfix_expression)) { tree fn = get_first_fn (postfix_expression); if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) fn = OVL_CURRENT (TREE_OPERAND (fn, 0)); /* Only do argument dependent lookup if regular lookup does not find a set of member functions. [basic.lookup.koenig]/2a */ if (!DECL_FUNCTION_MEMBER_P (fn)) { koenig_p = true; postfix_expression = perform_koenig_lookup (postfix_expression, args); } } } if (TREE_CODE (postfix_expression) == COMPONENT_REF) { tree instance = TREE_OPERAND (postfix_expression, 0); tree fn = TREE_OPERAND (postfix_expression, 1); if (processing_template_decl && (type_dependent_expression_p (instance) || (!BASELINK_P (fn) && TREE_CODE (fn) != FIELD_DECL) || type_dependent_expression_p (fn) || any_type_dependent_arguments_p (args))) { postfix_expression = build_nt_call_list (postfix_expression, args); break; } if (BASELINK_P (fn)) postfix_expression = (build_new_method_call (instance, fn, args, NULL_TREE, (idk == CP_ID_KIND_QUALIFIED ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL), /*fn_p=*/NULL, tf_warning_or_error)); else postfix_expression = finish_call_expr (postfix_expression, args, /*disallow_virtual=*/false, /*koenig_p=*/false, tf_warning_or_error); } else if (TREE_CODE (postfix_expression) == OFFSET_REF || TREE_CODE (postfix_expression) == MEMBER_REF || TREE_CODE (postfix_expression) == DOTSTAR_EXPR) postfix_expression = (build_offset_ref_call_from_tree (postfix_expression, args)); else if (idk == CP_ID_KIND_QUALIFIED) /* A call to a static class member, or a namespace-scope function. */ postfix_expression = finish_call_expr (postfix_expression, args, /*disallow_virtual=*/true, koenig_p, tf_warning_or_error); else /* All other function calls. */ postfix_expression = finish_call_expr (postfix_expression, args, /*disallow_virtual=*/false, koenig_p, tf_warning_or_error); /* The POSTFIX_EXPRESSION is certainly no longer an id. */ idk = CP_ID_KIND_NONE; } break; case CPP_DOT: case CPP_DEREF: /* postfix-expression . template [opt] id-expression postfix-expression . pseudo-destructor-name postfix-expression -> template [opt] id-expression postfix-expression -> pseudo-destructor-name */ /* Consume the `.' or `->' operator. */ cp_lexer_consume_token (parser->lexer); postfix_expression = cp_parser_postfix_dot_deref_expression (parser, token->type, postfix_expression, false, &idk); is_member_access = true; break; case CPP_PLUS_PLUS: /* postfix-expression ++ */ /* Consume the `++' token. */ cp_lexer_consume_token (parser->lexer); /* Generate a representation for the complete expression. */ postfix_expression = finish_increment_expr (postfix_expression, POSTINCREMENT_EXPR); /* Increments may not appear in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "an increment")) postfix_expression = error_mark_node; idk = CP_ID_KIND_NONE; is_member_access = false; break; case CPP_MINUS_MINUS: /* postfix-expression -- */ /* Consume the `--' token. */ cp_lexer_consume_token (parser->lexer); /* Generate a representation for the complete expression. */ postfix_expression = finish_increment_expr (postfix_expression, POSTDECREMENT_EXPR); /* Decrements may not appear in constant-expressions. */ if (cp_parser_non_integral_constant_expression (parser, "a decrement")) postfix_expression = error_mark_node; idk = CP_ID_KIND_NONE; is_member_access = false; break; default: if (member_access_only_p) return is_member_access? postfix_expression : error_mark_node; else return postfix_expression; } } /* We should never get here. */ gcc_unreachable (); return error_mark_node; } /* A subroutine of cp_parser_postfix_expression that also gets hijacked by cp_parser_builtin_offsetof. We're looking for postfix-expression [ expression ] FOR_OFFSETOF is set if we're being called in that context, which changes how we deal with integer constant expressions. */ static tree cp_parser_postfix_open_square_expression (cp_parser *parser, tree postfix_expression, bool for_offsetof) { tree index; /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the index expression. */ /* ??? For offsetof, there is a question of what to allow here. If offsetof is not being used in an integral constant expression context, then we *could* get the right answer by computing the value at runtime. If we are in an integral constant expression context, then we might could accept any constant expression; hard to say without analysis. Rather than open the barn door too wide right away, allow only integer constant expressions here. */ if (for_offsetof) index = cp_parser_constant_expression (parser, false, NULL); else index = cp_parser_expression (parser, /*cast_p=*/false); /* Look for the closing `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); /* Build the ARRAY_REF. */ postfix_expression = grok_array_decl (postfix_expression, index); /* When not doing offsetof, array references are not permitted in constant-expressions. */ if (!for_offsetof && (cp_parser_non_integral_constant_expression (parser, "an array reference"))) postfix_expression = error_mark_node; return postfix_expression; } /* A subroutine of cp_parser_postfix_expression that also gets hijacked by cp_parser_builtin_offsetof. We're looking for postfix-expression . template [opt] id-expression postfix-expression . pseudo-destructor-name postfix-expression -> template [opt] id-expression postfix-expression -> pseudo-destructor-name FOR_OFFSETOF is set if we're being called in that context. That sorta limits what of the above we'll actually accept, but nevermind. TOKEN_TYPE is the "." or "->" token, which will already have been removed from the stream. */ static tree cp_parser_postfix_dot_deref_expression (cp_parser *parser, enum cpp_ttype token_type, tree postfix_expression, bool for_offsetof, cp_id_kind *idk) { tree name; bool dependent_p; bool pseudo_destructor_p; tree scope = NULL_TREE; /* If this is a `->' operator, dereference the pointer. */ if (token_type == CPP_DEREF) postfix_expression = build_x_arrow (postfix_expression); /* Check to see whether or not the expression is type-dependent. */ dependent_p = type_dependent_expression_p (postfix_expression); /* The identifier following the `->' or `.' is not qualified. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; *idk = CP_ID_KIND_NONE; /* Enter the scope corresponding to the type of the object given by the POSTFIX_EXPRESSION. */ if (!dependent_p && TREE_TYPE (postfix_expression) != NULL_TREE) { scope = TREE_TYPE (postfix_expression); /* According to the standard, no expression should ever have reference type. Unfortunately, we do not currently match the standard in this respect in that our internal representation of an expression may have reference type even when the standard says it does not. Therefore, we have to manually obtain the underlying type here. */ scope = non_reference (scope); /* The type of the POSTFIX_EXPRESSION must be complete. */ if (scope == unknown_type_node) { error ("%qE does not have class type", postfix_expression); scope = NULL_TREE; } else scope = complete_type_or_else (scope, NULL_TREE); /* Let the name lookup machinery know that we are processing a class member access expression. */ parser->context->object_type = scope; /* If something went wrong, we want to be able to discern that case, as opposed to the case where there was no SCOPE due to the type of expression being dependent. */ if (!scope) scope = error_mark_node; /* If the SCOPE was erroneous, make the various semantic analysis functions exit quickly -- and without issuing additional error messages. */ if (scope == error_mark_node) postfix_expression = error_mark_node; } /* Assume this expression is not a pseudo-destructor access. */ pseudo_destructor_p = false; /* If the SCOPE is a scalar type, then, if this is a valid program, we must be looking at a pseudo-destructor-name. If POSTFIX_EXPRESSION is type dependent, it can be pseudo-destructor-name or something else. Try to parse it as pseudo-destructor-name first. */ if ((scope && SCALAR_TYPE_P (scope)) || dependent_p) { tree s; tree type; cp_parser_parse_tentatively (parser); /* Parse the pseudo-destructor-name. */ s = NULL_TREE; cp_parser_pseudo_destructor_name (parser, &s, &type); if (dependent_p && (cp_parser_error_occurred (parser) || TREE_CODE (type) != TYPE_DECL || !SCALAR_TYPE_P (TREE_TYPE (type)))) cp_parser_abort_tentative_parse (parser); else if (cp_parser_parse_definitely (parser)) { pseudo_destructor_p = true; postfix_expression = finish_pseudo_destructor_expr (postfix_expression, s, TREE_TYPE (type)); } } if (!pseudo_destructor_p) { /* If the SCOPE is not a scalar type, we are looking at an ordinary class member access expression, rather than a pseudo-destructor-name. */ bool template_p; /* Parse the id-expression. */ name = (cp_parser_id_expression (parser, cp_parser_optional_template_keyword (parser), /*check_dependency_p=*/true, &template_p, /*declarator_p=*/false, /*optional_p=*/false)); /* In general, build a SCOPE_REF if the member name is qualified. However, if the name was not dependent and has already been resolved; there is no need to build the SCOPE_REF. For example; struct X { void f(); }; template void f(T* t) { t->X::f(); } Even though "t" is dependent, "X::f" is not and has been resolved to a BASELINK; there is no need to include scope information. */ /* But we do need to remember that there was an explicit scope for virtual function calls. */ if (parser->scope) *idk = CP_ID_KIND_QUALIFIED; /* If the name is a template-id that names a type, we will get a TYPE_DECL here. That is invalid code. */ if (TREE_CODE (name) == TYPE_DECL) { error ("invalid use of %qD", name); postfix_expression = error_mark_node; } else { if (name != error_mark_node && !BASELINK_P (name) && parser->scope) { name = build_qualified_name (/*type=*/NULL_TREE, parser->scope, name, template_p); parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; } if (scope && name && BASELINK_P (name)) adjust_result_of_qualified_name_lookup (name, BINFO_TYPE (BASELINK_ACCESS_BINFO (name)), scope); postfix_expression = finish_class_member_access_expr (postfix_expression, name, template_p, tf_warning_or_error); } } /* We no longer need to look up names in the scope of the object on the left-hand side of the `.' or `->' operator. */ parser->context->object_type = NULL_TREE; /* Outside of offsetof, these operators may not appear in constant-expressions. */ if (!for_offsetof && (cp_parser_non_integral_constant_expression (parser, token_type == CPP_DEREF ? "'->'" : "`.'"))) postfix_expression = error_mark_node; return postfix_expression; } /* Parse a parenthesized expression-list. expression-list: assignment-expression expression-list, assignment-expression attribute-list: expression-list identifier identifier, expression-list CAST_P is true if this expression is the target of a cast. ALLOW_EXPANSION_P is true if this expression allows expansion of an argument pack. Returns a TREE_LIST. The TREE_VALUE of each node is a representation of an assignment-expression. Note that a TREE_LIST is returned even if there is only a single expression in the list. error_mark_node is returned if the ( and or ) are missing. NULL_TREE is returned on no expressions. The parentheses are eaten. IS_ATTRIBUTE_LIST is true if this is really an attribute list being parsed. If NON_CONSTANT_P is non-NULL, *NON_CONSTANT_P indicates whether or not all of the expressions in the list were constant. */ static tree cp_parser_parenthesized_expression_list (cp_parser* parser, bool is_attribute_list, bool cast_p, bool allow_expansion_p, bool *non_constant_p) { tree expression_list = NULL_TREE; bool fold_expr_p = is_attribute_list; tree identifier = NULL_TREE; bool saved_greater_than_is_operator_p; /* Assume all the expressions will be constant. */ if (non_constant_p) *non_constant_p = false; if (!cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) return error_mark_node; /* Within a parenthesized expression, a `>' token is always the greater-than operator. */ saved_greater_than_is_operator_p = parser->greater_than_is_operator_p; parser->greater_than_is_operator_p = true; /* Consume expressions until there are no more. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) while (true) { tree expr; /* At the beginning of attribute lists, check to see if the next token is an identifier. */ if (is_attribute_list && cp_lexer_peek_token (parser->lexer)->type == CPP_NAME) { cp_token *token; /* Consume the identifier. */ token = cp_lexer_consume_token (parser->lexer); /* Save the identifier. */ identifier = token->u.value; } else { /* Parse the next assignment-expression. */ if (non_constant_p) { bool expr_non_constant_p; expr = (cp_parser_constant_expression (parser, /*allow_non_constant_p=*/true, &expr_non_constant_p)); if (expr_non_constant_p) *non_constant_p = true; } else expr = cp_parser_assignment_expression (parser, cast_p); if (fold_expr_p) expr = fold_non_dependent_expr (expr); /* If we have an ellipsis, then this is an expression expansion. */ if (allow_expansion_p && cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...'. */ cp_lexer_consume_token (parser->lexer); /* Build the argument pack. */ expr = make_pack_expansion (expr); } /* Add it to the list. We add error_mark_node expressions to the list, so that we can still tell if the correct form for a parenthesized expression-list is found. That gives better errors. */ expression_list = tree_cons (NULL_TREE, expr, expression_list); if (expr == error_mark_node) goto skip_comma; } /* After the first item, attribute lists look the same as expression lists. */ is_attribute_list = false; get_comma:; /* If the next token isn't a `,', then we are done. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Otherwise, consume the `,' and keep going. */ cp_lexer_consume_token (parser->lexer); } if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) { int ending; skip_comma:; /* We try and resync to an unnested comma, as that will give the user better diagnostics. */ ending = cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/true, /*consume_paren=*/true); if (ending < 0) goto get_comma; if (!ending) { parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; return error_mark_node; } } parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; /* We built up the list in reverse order so we must reverse it now. */ expression_list = nreverse (expression_list); if (identifier) expression_list = tree_cons (NULL_TREE, identifier, expression_list); return expression_list; } /* Parse a pseudo-destructor-name. pseudo-destructor-name: :: [opt] nested-name-specifier [opt] type-name :: ~ type-name :: [opt] nested-name-specifier template template-id :: ~ type-name :: [opt] nested-name-specifier [opt] ~ type-name If either of the first two productions is used, sets *SCOPE to the TYPE specified before the final `::'. Otherwise, *SCOPE is set to NULL_TREE. *TYPE is set to the TYPE_DECL for the final type-name, or ERROR_MARK_NODE if the parse fails. */ static void cp_parser_pseudo_destructor_name (cp_parser* parser, tree* scope, tree* type) { bool nested_name_specifier_p; /* Assume that things will not work out. */ *type = error_mark_node; /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/true); /* Look for the optional nested-name-specifier. */ nested_name_specifier_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true) != NULL_TREE); /* Now, if we saw a nested-name-specifier, we might be doing the second production. */ if (nested_name_specifier_p && cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) { /* Consume the `template' keyword. */ cp_lexer_consume_token (parser->lexer); /* Parse the template-id. */ cp_parser_template_id (parser, /*template_keyword_p=*/true, /*check_dependency_p=*/false, /*is_declaration=*/true); /* Look for the `::' token. */ cp_parser_require (parser, CPP_SCOPE, "`::'"); } /* If the next token is not a `~', then there might be some additional qualification. */ else if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMPL)) { /* At this point, we're looking for "type-name :: ~". The type-name must not be a class-name, since this is a pseudo-destructor. So, it must be either an enum-name, or a typedef-name -- both of which are just identifiers. So, we peek ahead to check that the "::" and "~" tokens are present; if they are not, then we can avoid calling type_name. */ if (cp_lexer_peek_token (parser->lexer)->type != CPP_NAME || cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE || cp_lexer_peek_nth_token (parser->lexer, 3)->type != CPP_COMPL) { cp_parser_error (parser, "non-scalar type"); return; } /* Look for the type-name. */ *scope = TREE_TYPE (cp_parser_nonclass_name (parser)); if (*scope == error_mark_node) return; /* Look for the `::' token. */ cp_parser_require (parser, CPP_SCOPE, "`::'"); } else *scope = NULL_TREE; /* Look for the `~'. */ cp_parser_require (parser, CPP_COMPL, "`~'"); /* Look for the type-name again. We are not responsible for checking that it matches the first type-name. */ *type = cp_parser_nonclass_name (parser); } /* Parse a unary-expression. unary-expression: postfix-expression ++ cast-expression -- cast-expression unary-operator cast-expression sizeof unary-expression sizeof ( type-id ) new-expression delete-expression GNU Extensions: unary-expression: __extension__ cast-expression __alignof__ unary-expression __alignof__ ( type-id ) __real__ cast-expression __imag__ cast-expression && identifier ADDRESS_P is true iff the unary-expression is appearing as the operand of the `&' operator. CAST_P is true if this expression is the target of a cast. Returns a representation of the expression. */ static tree cp_parser_unary_expression (cp_parser *parser, bool address_p, bool cast_p) { cp_token *token; enum tree_code unary_operator; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Some keywords give away the kind of expression. */ if (token->type == CPP_KEYWORD) { enum rid keyword = token->keyword; switch (keyword) { case RID_ALIGNOF: case RID_SIZEOF: { tree operand; enum tree_code op; op = keyword == RID_ALIGNOF ? ALIGNOF_EXPR : SIZEOF_EXPR; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); /* Parse the operand. */ operand = cp_parser_sizeof_operand (parser, keyword); if (TYPE_P (operand)) return cxx_sizeof_or_alignof_type (operand, op, true); else return cxx_sizeof_or_alignof_expr (operand, op, true); } case RID_NEW: return cp_parser_new_expression (parser); case RID_DELETE: return cp_parser_delete_expression (parser); case RID_EXTENSION: { /* The saved value of the PEDANTIC flag. */ int saved_pedantic; tree expr; /* Save away the PEDANTIC flag. */ cp_parser_extension_opt (parser, &saved_pedantic); /* Parse the cast-expression. */ expr = cp_parser_simple_cast_expression (parser); /* Restore the PEDANTIC flag. */ pedantic = saved_pedantic; return expr; } case RID_REALPART: case RID_IMAGPART: { tree expression; /* Consume the `__real__' or `__imag__' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the cast-expression. */ expression = cp_parser_simple_cast_expression (parser); /* Create the complete representation. */ return build_x_unary_op ((keyword == RID_REALPART ? REALPART_EXPR : IMAGPART_EXPR), expression, tf_warning_or_error); } break; default: break; } } /* Look for the `:: new' and `:: delete', which also signal the beginning of a new-expression, or delete-expression, respectively. If the next token is `::', then it might be one of these. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) { enum rid keyword; /* See if the token after the `::' is one of the keywords in which we're interested. */ keyword = cp_lexer_peek_nth_token (parser->lexer, 2)->keyword; /* If it's `new', we have a new-expression. */ if (keyword == RID_NEW) return cp_parser_new_expression (parser); /* Similarly, for `delete'. */ else if (keyword == RID_DELETE) return cp_parser_delete_expression (parser); } /* Look for a unary operator. */ unary_operator = cp_parser_unary_operator (token); /* The `++' and `--' operators can be handled similarly, even though they are not technically unary-operators in the grammar. */ if (unary_operator == ERROR_MARK) { if (token->type == CPP_PLUS_PLUS) unary_operator = PREINCREMENT_EXPR; else if (token->type == CPP_MINUS_MINUS) unary_operator = PREDECREMENT_EXPR; /* Handle the GNU address-of-label extension. */ else if (cp_parser_allow_gnu_extensions_p (parser) && token->type == CPP_AND_AND) { tree identifier; tree expression; /* Consume the '&&' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the identifier. */ identifier = cp_parser_identifier (parser); /* Create an expression representing the address. */ expression = finish_label_address_expr (identifier); if (cp_parser_non_integral_constant_expression (parser, "the address of a label")) expression = error_mark_node; return expression; } } if (unary_operator != ERROR_MARK) { tree cast_expression; tree expression = error_mark_node; const char *non_constant_p = NULL; /* Consume the operator token. */ token = cp_lexer_consume_token (parser->lexer); /* Parse the cast-expression. */ cast_expression = cp_parser_cast_expression (parser, unary_operator == ADDR_EXPR, /*cast_p=*/false); /* Now, build an appropriate representation. */ switch (unary_operator) { case INDIRECT_REF: non_constant_p = "`*'"; expression = build_x_indirect_ref (cast_expression, "unary *", tf_warning_or_error); break; case ADDR_EXPR: non_constant_p = "`&'"; /* Fall through. */ case BIT_NOT_EXPR: expression = build_x_unary_op (unary_operator, cast_expression, tf_warning_or_error); break; case PREINCREMENT_EXPR: case PREDECREMENT_EXPR: non_constant_p = (unary_operator == PREINCREMENT_EXPR ? "`++'" : "`--'"); /* Fall through. */ case UNARY_PLUS_EXPR: case NEGATE_EXPR: case TRUTH_NOT_EXPR: expression = finish_unary_op_expr (unary_operator, cast_expression); break; default: gcc_unreachable (); } if (non_constant_p && cp_parser_non_integral_constant_expression (parser, non_constant_p)) expression = error_mark_node; return expression; } return cp_parser_postfix_expression (parser, address_p, cast_p, /*member_access_only_p=*/false); } /* Returns ERROR_MARK if TOKEN is not a unary-operator. If TOKEN is a unary-operator, the corresponding tree code is returned. */ static enum tree_code cp_parser_unary_operator (cp_token* token) { switch (token->type) { case CPP_MULT: return INDIRECT_REF; case CPP_AND: return ADDR_EXPR; case CPP_PLUS: return UNARY_PLUS_EXPR; case CPP_MINUS: return NEGATE_EXPR; case CPP_NOT: return TRUTH_NOT_EXPR; case CPP_COMPL: return BIT_NOT_EXPR; default: return ERROR_MARK; } } /* Parse a new-expression. new-expression: :: [opt] new new-placement [opt] new-type-id new-initializer [opt] :: [opt] new new-placement [opt] ( type-id ) new-initializer [opt] Returns a representation of the expression. */ static tree cp_parser_new_expression (cp_parser* parser) { bool global_scope_p; tree placement; tree type; tree initializer; tree nelts; /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the `new' operator. */ cp_parser_require_keyword (parser, RID_NEW, "`new'"); /* There's no easy way to tell a new-placement from the `( type-id )' construct. */ cp_parser_parse_tentatively (parser); /* Look for a new-placement. */ placement = cp_parser_new_placement (parser); /* If that didn't work out, there's no new-placement. */ if (!cp_parser_parse_definitely (parser)) placement = NULL_TREE; /* If the next token is a `(', then we have a parenthesized type-id. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the type-id. */ type = cp_parser_type_id (parser); /* Look for the closing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* There should not be a direct-new-declarator in this production, but GCC used to allowed this, so we check and emit a sensible error message for this case. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) { error ("array bound forbidden after parenthesized type-id"); inform ("try removing the parentheses around the type-id"); cp_parser_direct_new_declarator (parser); } nelts = NULL_TREE; } /* Otherwise, there must be a new-type-id. */ else type = cp_parser_new_type_id (parser, &nelts); /* If the next token is a `(', then we have a new-initializer. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) initializer = cp_parser_new_initializer (parser); else initializer = NULL_TREE; /* A new-expression may not appear in an integral constant expression. */ if (cp_parser_non_integral_constant_expression (parser, "`new'")) return error_mark_node; /* Create a representation of the new-expression. */ return build_new (placement, type, nelts, initializer, global_scope_p, tf_warning_or_error); } /* Parse a new-placement. new-placement: ( expression-list ) Returns the same representation as for an expression-list. */ static tree cp_parser_new_placement (cp_parser* parser) { tree expression_list; /* Parse the expression-list. */ expression_list = (cp_parser_parenthesized_expression_list (parser, false, /*cast_p=*/false, /*allow_expansion_p=*/true, /*non_constant_p=*/NULL)); return expression_list; } /* Parse a new-type-id. new-type-id: type-specifier-seq new-declarator [opt] Returns the TYPE allocated. If the new-type-id indicates an array type, *NELTS is set to the number of elements in the last array bound; the TYPE will not include the last array bound. */ static tree cp_parser_new_type_id (cp_parser* parser, tree *nelts) { cp_decl_specifier_seq type_specifier_seq; cp_declarator *new_declarator; cp_declarator *declarator; cp_declarator *outer_declarator; const char *saved_message; tree type; /* The type-specifier sequence must not contain type definitions. (It cannot contain declarations of new types either, but if they are not definitions we will catch that because they are not complete.) */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in a new-type-id"; /* Parse the type-specifier-seq. */ cp_parser_type_specifier_seq (parser, /*is_condition=*/false, &type_specifier_seq); /* Restore the old message. */ parser->type_definition_forbidden_message = saved_message; /* Parse the new-declarator. */ new_declarator = cp_parser_new_declarator_opt (parser); /* Determine the number of elements in the last array dimension, if any. */ *nelts = NULL_TREE; /* Skip down to the last array dimension. */ declarator = new_declarator; outer_declarator = NULL; while (declarator && (declarator->kind == cdk_pointer || declarator->kind == cdk_ptrmem)) { outer_declarator = declarator; declarator = declarator->declarator; } while (declarator && declarator->kind == cdk_array && declarator->declarator && declarator->declarator->kind == cdk_array) { outer_declarator = declarator; declarator = declarator->declarator; } if (declarator && declarator->kind == cdk_array) { *nelts = declarator->u.array.bounds; if (*nelts == error_mark_node) *nelts = integer_one_node; if (outer_declarator) outer_declarator->declarator = declarator->declarator; else new_declarator = NULL; } type = groktypename (&type_specifier_seq, new_declarator); return type; } /* Parse an (optional) new-declarator. new-declarator: ptr-operator new-declarator [opt] direct-new-declarator Returns the declarator. */ static cp_declarator * cp_parser_new_declarator_opt (cp_parser* parser) { enum tree_code code; tree type; cp_cv_quals cv_quals; /* We don't know if there's a ptr-operator next, or not. */ cp_parser_parse_tentatively (parser); /* Look for a ptr-operator. */ code = cp_parser_ptr_operator (parser, &type, &cv_quals); /* If that worked, look for more new-declarators. */ if (cp_parser_parse_definitely (parser)) { cp_declarator *declarator; /* Parse another optional declarator. */ declarator = cp_parser_new_declarator_opt (parser); return cp_parser_make_indirect_declarator (code, type, cv_quals, declarator); } /* If the next token is a `[', there is a direct-new-declarator. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) return cp_parser_direct_new_declarator (parser); return NULL; } /* Parse a direct-new-declarator. direct-new-declarator: [ expression ] direct-new-declarator [constant-expression] */ static cp_declarator * cp_parser_direct_new_declarator (cp_parser* parser) { cp_declarator *declarator = NULL; while (true) { tree expression; /* Look for the opening `['. */ cp_parser_require (parser, CPP_OPEN_SQUARE, "`['"); /* The first expression is not required to be constant. */ if (!declarator) { expression = cp_parser_expression (parser, /*cast_p=*/false); /* The standard requires that the expression have integral type. DR 74 adds enumeration types. We believe that the real intent is that these expressions be handled like the expression in a `switch' condition, which also allows classes with a single conversion to integral or enumeration type. */ if (!processing_template_decl) { expression = build_expr_type_conversion (WANT_INT | WANT_ENUM, expression, /*complain=*/true); if (!expression) { error ("expression in new-declarator must have integral " "or enumeration type"); expression = error_mark_node; } } } /* But all the other expressions must be. */ else expression = cp_parser_constant_expression (parser, /*allow_non_constant=*/false, NULL); /* Look for the closing `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); /* Add this bound to the declarator. */ declarator = make_array_declarator (declarator, expression); /* If the next token is not a `[', then there are no more bounds. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_SQUARE)) break; } return declarator; } /* Parse a new-initializer. new-initializer: ( expression-list [opt] ) Returns a representation of the expression-list. If there is no expression-list, VOID_ZERO_NODE is returned. */ static tree cp_parser_new_initializer (cp_parser* parser) { tree expression_list; expression_list = (cp_parser_parenthesized_expression_list (parser, false, /*cast_p=*/false, /*allow_expansion_p=*/true, /*non_constant_p=*/NULL)); if (!expression_list) expression_list = void_zero_node; return expression_list; } /* Parse a delete-expression. delete-expression: :: [opt] delete cast-expression :: [opt] delete [ ] cast-expression Returns a representation of the expression. */ static tree cp_parser_delete_expression (cp_parser* parser) { bool global_scope_p; bool array_p; tree expression; /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the `delete' keyword. */ cp_parser_require_keyword (parser, RID_DELETE, "`delete'"); /* See if the array syntax is in use. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_SQUARE)) { /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `]' token. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); /* Remember that this is the `[]' construct. */ array_p = true; } else array_p = false; /* Parse the cast-expression. */ expression = cp_parser_simple_cast_expression (parser); /* A delete-expression may not appear in an integral constant expression. */ if (cp_parser_non_integral_constant_expression (parser, "`delete'")) return error_mark_node; return delete_sanity (expression, NULL_TREE, array_p, global_scope_p); } /* Parse a cast-expression. cast-expression: unary-expression ( type-id ) cast-expression ADDRESS_P is true iff the unary-expression is appearing as the operand of the `&' operator. CAST_P is true if this expression is the target of a cast. Returns a representation of the expression. */ static tree cp_parser_cast_expression (cp_parser *parser, bool address_p, bool cast_p) { /* If it's a `(', then we might be looking at a cast. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { tree type = NULL_TREE; tree expr = NULL_TREE; bool compound_literal_p; const char *saved_message; /* There's no way to know yet whether or not this is a cast. For example, `(int (3))' is a unary-expression, while `(int) 3' is a cast. So, we resort to parsing tentatively. */ cp_parser_parse_tentatively (parser); /* Types may not be defined in a cast. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in casts"; /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* A very tricky bit is that `(struct S) { 3 }' is a compound-literal (which we permit in C++ as an extension). But, that construct is not a cast-expression -- it is a postfix-expression. (The reason is that `(struct S) { 3 }.i' is legal; if the compound-literal were a cast-expression, you'd need an extra set of parentheses.) But, if we parse the type-id, and it happens to be a class-specifier, then we will commit to the parse at that point, because we cannot undo the action that is done when creating a new class. So, then we cannot back up and do a postfix-expression. Therefore, we scan ahead to the closing `)', and check to see if the token after the `)' is a `{'. If so, we are not looking at a cast-expression. Save tokens so that we can put them back. */ cp_lexer_save_tokens (parser->lexer); /* Skip tokens until the next token is a closing parenthesis. If we find the closing `)', and the next token is a `{', then we are looking at a compound-literal. */ compound_literal_p = (cp_parser_skip_to_closing_parenthesis (parser, false, false, /*consume_paren=*/true) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)); /* Roll back the tokens we skipped. */ cp_lexer_rollback_tokens (parser->lexer); /* If we were looking at a compound-literal, simulate an error so that the call to cp_parser_parse_definitely below will fail. */ if (compound_literal_p) cp_parser_simulate_error (parser); else { bool saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; /* Look for the type-id. */ type = cp_parser_type_id (parser); /* Look for the closing `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; } /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; /* If ok so far, parse the dependent expression. We cannot be sure it is a cast. Consider `(T ())'. It is a parenthesized ctor of T, but looks like a cast to function returning T without a dependent expression. */ if (!cp_parser_error_occurred (parser)) expr = cp_parser_cast_expression (parser, /*address_p=*/false, /*cast_p=*/true); if (cp_parser_parse_definitely (parser)) { /* Warn about old-style casts, if so requested. */ if (warn_old_style_cast && !in_system_header && !VOID_TYPE_P (type) && current_lang_name != lang_name_c) warning (OPT_Wold_style_cast, "use of old-style cast"); /* Only type conversions to integral or enumeration types can be used in constant-expressions. */ if (!cast_valid_in_integral_constant_expression_p (type) && (cp_parser_non_integral_constant_expression (parser, "a cast to a type other than an integral or " "enumeration type"))) return error_mark_node; /* Perform the cast. */ expr = build_c_cast (type, expr); return expr; } } /* If we get here, then it's not a cast, so it must be a unary-expression. */ return cp_parser_unary_expression (parser, address_p, cast_p); } /* Parse a binary expression of the general form: pm-expression: cast-expression pm-expression .* cast-expression pm-expression ->* cast-expression multiplicative-expression: pm-expression multiplicative-expression * pm-expression multiplicative-expression / pm-expression multiplicative-expression % pm-expression additive-expression: multiplicative-expression additive-expression + multiplicative-expression additive-expression - multiplicative-expression shift-expression: additive-expression shift-expression << additive-expression shift-expression >> additive-expression relational-expression: shift-expression relational-expression < shift-expression relational-expression > shift-expression relational-expression <= shift-expression relational-expression >= shift-expression GNU Extension: relational-expression: relational-expression ? shift-expression equality-expression: relational-expression equality-expression == relational-expression equality-expression != relational-expression and-expression: equality-expression and-expression & equality-expression exclusive-or-expression: and-expression exclusive-or-expression ^ and-expression inclusive-or-expression: exclusive-or-expression inclusive-or-expression | exclusive-or-expression logical-and-expression: inclusive-or-expression logical-and-expression && inclusive-or-expression logical-or-expression: logical-and-expression logical-or-expression || logical-and-expression All these are implemented with a single function like: binary-expression: simple-cast-expression binary-expression binary-expression CAST_P is true if this expression is the target of a cast. The binops_by_token map is used to get the tree codes for each type. binary-expressions are associated according to a precedence table. */ #define TOKEN_PRECEDENCE(token) \ (((token->type == CPP_GREATER \ || ((cxx_dialect != cxx98) && token->type == CPP_RSHIFT)) \ && !parser->greater_than_is_operator_p) \ ? PREC_NOT_OPERATOR \ : binops_by_token[token->type].prec) static tree cp_parser_binary_expression (cp_parser* parser, bool cast_p) { cp_parser_expression_stack stack; cp_parser_expression_stack_entry *sp = &stack[0]; tree lhs, rhs; cp_token *token; enum tree_code tree_type, lhs_type, rhs_type; enum cp_parser_prec prec = PREC_NOT_OPERATOR, new_prec, lookahead_prec; bool overloaded_p; /* Parse the first expression. */ lhs = cp_parser_cast_expression (parser, /*address_p=*/false, cast_p); lhs_type = ERROR_MARK; for (;;) { /* Get an operator token. */ token = cp_lexer_peek_token (parser->lexer); if (warn_cxx0x_compat && token->type == CPP_RSHIFT && !parser->greater_than_is_operator_p) { warning (OPT_Wc__0x_compat, "%H%<>>%> operator will be treated as two right angle brackets in C++0x", &token->location); warning (OPT_Wc__0x_compat, "suggest parentheses around %<>>%> expression"); } new_prec = TOKEN_PRECEDENCE (token); /* Popping an entry off the stack means we completed a subexpression: - either we found a token which is not an operator (`>' where it is not an operator, or prec == PREC_NOT_OPERATOR), in which case popping will happen repeatedly; - or, we found an operator which has lower priority. This is the case where the recursive descent *ascends*, as in `3 * 4 + 5' after parsing `3 * 4'. */ if (new_prec <= prec) { if (sp == stack) break; else goto pop; } get_rhs: tree_type = binops_by_token[token->type].tree_type; /* We used the operator token. */ cp_lexer_consume_token (parser->lexer); /* Extract another operand. It may be the RHS of this expression or the LHS of a new, higher priority expression. */ rhs = cp_parser_simple_cast_expression (parser); rhs_type = ERROR_MARK; /* Get another operator token. Look up its precedence to avoid building a useless (immediately popped) stack entry for common cases such as 3 + 4 + 5 or 3 * 4 + 5. */ token = cp_lexer_peek_token (parser->lexer); lookahead_prec = TOKEN_PRECEDENCE (token); if (lookahead_prec > new_prec) { /* ... and prepare to parse the RHS of the new, higher priority expression. Since precedence levels on the stack are monotonically increasing, we do not have to care about stack overflows. */ sp->prec = prec; sp->tree_type = tree_type; sp->lhs = lhs; sp->lhs_type = lhs_type; sp++; lhs = rhs; lhs_type = rhs_type; prec = new_prec; new_prec = lookahead_prec; goto get_rhs; pop: /* If the stack is not empty, we have parsed into LHS the right side (`4' in the example above) of an expression we had suspended. We can use the information on the stack to recover the LHS (`3') from the stack together with the tree code (`MULT_EXPR'), and the precedence of the higher level subexpression (`PREC_ADDITIVE_EXPRESSION'). TOKEN is the CPP_PLUS token, which will be used to actually build the additive expression. */ --sp; prec = sp->prec; tree_type = sp->tree_type; rhs = lhs; rhs_type = lhs_type; lhs = sp->lhs; lhs_type = sp->lhs_type; } overloaded_p = false; lhs = build_x_binary_op (tree_type, lhs, lhs_type, rhs, rhs_type, &overloaded_p, tf_warning_or_error); lhs_type = tree_type; /* If the binary operator required the use of an overloaded operator, then this expression cannot be an integral constant-expression. An overloaded operator can be used even if both operands are otherwise permissible in an integral constant-expression if at least one of the operands is of enumeration type. */ if (overloaded_p && (cp_parser_non_integral_constant_expression (parser, "calls to overloaded operators"))) return error_mark_node; } return lhs; } /* Parse the `? expression : assignment-expression' part of a conditional-expression. The LOGICAL_OR_EXPR is the logical-or-expression that started the conditional-expression. Returns a representation of the entire conditional-expression. This routine is used by cp_parser_assignment_expression. ? expression : assignment-expression GNU Extensions: ? : assignment-expression */ static tree cp_parser_question_colon_clause (cp_parser* parser, tree logical_or_expr) { tree expr; tree assignment_expr; /* Consume the `?' token. */ cp_lexer_consume_token (parser->lexer); if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_COLON)) /* Implicit true clause. */ expr = NULL_TREE; else /* Parse the expression. */ expr = cp_parser_expression (parser, /*cast_p=*/false); /* The next token should be a `:'. */ cp_parser_require (parser, CPP_COLON, "`:'"); /* Parse the assignment-expression. */ assignment_expr = cp_parser_assignment_expression (parser, /*cast_p=*/false); /* Build the conditional-expression. */ return build_x_conditional_expr (logical_or_expr, expr, assignment_expr, tf_warning_or_error); } /* Parse an assignment-expression. assignment-expression: conditional-expression logical-or-expression assignment-operator assignment_expression throw-expression CAST_P is true if this expression is the target of a cast. Returns a representation for the expression. */ static tree cp_parser_assignment_expression (cp_parser* parser, bool cast_p) { tree expr; /* If the next token is the `throw' keyword, then we're looking at a throw-expression. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_THROW)) expr = cp_parser_throw_expression (parser); /* Otherwise, it must be that we are looking at a logical-or-expression. */ else { /* Parse the binary expressions (logical-or-expression). */ expr = cp_parser_binary_expression (parser, cast_p); /* If the next token is a `?' then we're actually looking at a conditional-expression. */ if (cp_lexer_next_token_is (parser->lexer, CPP_QUERY)) return cp_parser_question_colon_clause (parser, expr); else { enum tree_code assignment_operator; /* If it's an assignment-operator, we're using the second production. */ assignment_operator = cp_parser_assignment_operator_opt (parser); if (assignment_operator != ERROR_MARK) { tree rhs; /* Parse the right-hand side of the assignment. */ rhs = cp_parser_assignment_expression (parser, cast_p); /* An assignment may not appear in a constant-expression. */ if (cp_parser_non_integral_constant_expression (parser, "an assignment")) return error_mark_node; /* Build the assignment expression. */ expr = build_x_modify_expr (expr, assignment_operator, rhs, tf_warning_or_error); } } } return expr; } /* Parse an (optional) assignment-operator. assignment-operator: one of = *= /= %= += -= >>= <<= &= ^= |= GNU Extension: assignment-operator: one of ?= If the next token is an assignment operator, the corresponding tree code is returned, and the token is consumed. For example, for `+=', PLUS_EXPR is returned. For `=' itself, the code returned is NOP_EXPR. For `/', TRUNC_DIV_EXPR is returned; for `%', TRUNC_MOD_EXPR is returned. If TOKEN is not an assignment operator, ERROR_MARK is returned. */ static enum tree_code cp_parser_assignment_operator_opt (cp_parser* parser) { enum tree_code op; cp_token *token; /* Peek at the next toen. */ token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_EQ: op = NOP_EXPR; break; case CPP_MULT_EQ: op = MULT_EXPR; break; case CPP_DIV_EQ: op = TRUNC_DIV_EXPR; break; case CPP_MOD_EQ: op = TRUNC_MOD_EXPR; break; case CPP_PLUS_EQ: op = PLUS_EXPR; break; case CPP_MINUS_EQ: op = MINUS_EXPR; break; case CPP_RSHIFT_EQ: op = RSHIFT_EXPR; break; case CPP_LSHIFT_EQ: op = LSHIFT_EXPR; break; case CPP_AND_EQ: op = BIT_AND_EXPR; break; case CPP_XOR_EQ: op = BIT_XOR_EXPR; break; case CPP_OR_EQ: op = BIT_IOR_EXPR; break; default: /* Nothing else is an assignment operator. */ op = ERROR_MARK; } /* If it was an assignment operator, consume it. */ if (op != ERROR_MARK) cp_lexer_consume_token (parser->lexer); return op; } /* Parse an expression. expression: assignment-expression expression , assignment-expression CAST_P is true if this expression is the target of a cast. Returns a representation of the expression. */ static tree cp_parser_expression (cp_parser* parser, bool cast_p) { tree expression = NULL_TREE; while (true) { tree assignment_expression; /* Parse the next assignment-expression. */ assignment_expression = cp_parser_assignment_expression (parser, cast_p); /* If this is the first assignment-expression, we can just save it away. */ if (!expression) expression = assignment_expression; else expression = build_x_compound_expr (expression, assignment_expression, tf_warning_or_error); /* If the next token is not a comma, then we are done with the expression. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); /* A comma operator cannot appear in a constant-expression. */ if (cp_parser_non_integral_constant_expression (parser, "a comma operator")) expression = error_mark_node; } return expression; } /* Parse a constant-expression. constant-expression: conditional-expression If ALLOW_NON_CONSTANT_P a non-constant expression is silently accepted. If ALLOW_NON_CONSTANT_P is true and the expression is not constant, *NON_CONSTANT_P is set to TRUE. If ALLOW_NON_CONSTANT_P is false, NON_CONSTANT_P should be NULL. */ static tree cp_parser_constant_expression (cp_parser* parser, bool allow_non_constant_p, bool *non_constant_p) { bool saved_integral_constant_expression_p; bool saved_allow_non_integral_constant_expression_p; bool saved_non_integral_constant_expression_p; tree expression; /* It might seem that we could simply parse the conditional-expression, and then check to see if it were TREE_CONSTANT. However, an expression that is TREE_CONSTANT is one that the compiler can figure out is constant, possibly after doing some simplifications or optimizations. The standard has a precise definition of constant-expression, and we must honor that, even though it is somewhat more restrictive. For example: int i[(2, 3)]; is not a legal declaration, because `(2, 3)' is not a constant-expression. The `,' operator is forbidden in a constant-expression. However, GCC's constant-folding machinery will fold this operation to an INTEGER_CST for `3'. */ /* Save the old settings. */ saved_integral_constant_expression_p = parser->integral_constant_expression_p; saved_allow_non_integral_constant_expression_p = parser->allow_non_integral_constant_expression_p; saved_non_integral_constant_expression_p = parser->non_integral_constant_expression_p; /* We are now parsing a constant-expression. */ parser->integral_constant_expression_p = true; parser->allow_non_integral_constant_expression_p = allow_non_constant_p; parser->non_integral_constant_expression_p = false; /* Although the grammar says "conditional-expression", we parse an "assignment-expression", which also permits "throw-expression" and the use of assignment operators. In the case that ALLOW_NON_CONSTANT_P is false, we get better errors than we would otherwise. In the case that ALLOW_NON_CONSTANT_P is true, it is actually essential that we look for an assignment-expression. For example, cp_parser_initializer_clauses uses this function to determine whether a particular assignment-expression is in fact constant. */ expression = cp_parser_assignment_expression (parser, /*cast_p=*/false); /* Restore the old settings. */ parser->integral_constant_expression_p = saved_integral_constant_expression_p; parser->allow_non_integral_constant_expression_p = saved_allow_non_integral_constant_expression_p; if (allow_non_constant_p) *non_constant_p = parser->non_integral_constant_expression_p; else if (parser->non_integral_constant_expression_p) expression = error_mark_node; parser->non_integral_constant_expression_p = saved_non_integral_constant_expression_p; return expression; } /* Parse __builtin_offsetof. offsetof-expression: "__builtin_offsetof" "(" type-id "," offsetof-member-designator ")" offsetof-member-designator: id-expression | offsetof-member-designator "." id-expression | offsetof-member-designator "[" expression "]" */ static tree cp_parser_builtin_offsetof (cp_parser *parser) { int save_ice_p, save_non_ice_p; tree type, expr; cp_id_kind dummy; /* We're about to accept non-integral-constant things, but will definitely yield an integral constant expression. Save and restore these values around our local parsing. */ save_ice_p = parser->integral_constant_expression_p; save_non_ice_p = parser->non_integral_constant_expression_p; /* Consume the "__builtin_offsetof" token. */ cp_lexer_consume_token (parser->lexer); /* Consume the opening `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the type-id. */ type = cp_parser_type_id (parser); /* Look for the `,'. */ cp_parser_require (parser, CPP_COMMA, "`,'"); /* Build the (type *)null that begins the traditional offsetof macro. */ expr = build_static_cast (build_pointer_type (type), null_pointer_node, tf_warning_or_error); /* Parse the offsetof-member-designator. We begin as if we saw "expr->". */ expr = cp_parser_postfix_dot_deref_expression (parser, CPP_DEREF, expr, true, &dummy); while (true) { cp_token *token = cp_lexer_peek_token (parser->lexer); switch (token->type) { case CPP_OPEN_SQUARE: /* offsetof-member-designator "[" expression "]" */ expr = cp_parser_postfix_open_square_expression (parser, expr, true); break; case CPP_DOT: /* offsetof-member-designator "." identifier */ cp_lexer_consume_token (parser->lexer); expr = cp_parser_postfix_dot_deref_expression (parser, CPP_DOT, expr, true, &dummy); break; case CPP_CLOSE_PAREN: /* Consume the ")" token. */ cp_lexer_consume_token (parser->lexer); goto success; default: /* Error. We know the following require will fail, but that gives the proper error message. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); cp_parser_skip_to_closing_parenthesis (parser, true, false, true); expr = error_mark_node; goto failure; } } success: /* If we're processing a template, we can't finish the semantics yet. Otherwise we can fold the entire expression now. */ if (processing_template_decl) expr = build1 (OFFSETOF_EXPR, size_type_node, expr); else expr = finish_offsetof (expr); failure: parser->integral_constant_expression_p = save_ice_p; parser->non_integral_constant_expression_p = save_non_ice_p; return expr; } /* Parse a trait expression. */ static tree cp_parser_trait_expr (cp_parser* parser, enum rid keyword) { cp_trait_kind kind; tree type1, type2 = NULL_TREE; bool binary = false; cp_decl_specifier_seq decl_specs; switch (keyword) { case RID_HAS_NOTHROW_ASSIGN: kind = CPTK_HAS_NOTHROW_ASSIGN; break; case RID_HAS_NOTHROW_CONSTRUCTOR: kind = CPTK_HAS_NOTHROW_CONSTRUCTOR; break; case RID_HAS_NOTHROW_COPY: kind = CPTK_HAS_NOTHROW_COPY; break; case RID_HAS_TRIVIAL_ASSIGN: kind = CPTK_HAS_TRIVIAL_ASSIGN; break; case RID_HAS_TRIVIAL_CONSTRUCTOR: kind = CPTK_HAS_TRIVIAL_CONSTRUCTOR; break; case RID_HAS_TRIVIAL_COPY: kind = CPTK_HAS_TRIVIAL_COPY; break; case RID_HAS_TRIVIAL_DESTRUCTOR: kind = CPTK_HAS_TRIVIAL_DESTRUCTOR; break; case RID_HAS_VIRTUAL_DESTRUCTOR: kind = CPTK_HAS_VIRTUAL_DESTRUCTOR; break; case RID_IS_ABSTRACT: kind = CPTK_IS_ABSTRACT; break; case RID_IS_BASE_OF: kind = CPTK_IS_BASE_OF; binary = true; break; case RID_IS_CLASS: kind = CPTK_IS_CLASS; break; case RID_IS_CONVERTIBLE_TO: kind = CPTK_IS_CONVERTIBLE_TO; binary = true; break; case RID_IS_EMPTY: kind = CPTK_IS_EMPTY; break; case RID_IS_ENUM: kind = CPTK_IS_ENUM; break; case RID_IS_POD: kind = CPTK_IS_POD; break; case RID_IS_POLYMORPHIC: kind = CPTK_IS_POLYMORPHIC; break; case RID_IS_UNION: kind = CPTK_IS_UNION; break; default: gcc_unreachable (); } /* Consume the token. */ cp_lexer_consume_token (parser->lexer); cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); type1 = cp_parser_type_id (parser); if (type1 == error_mark_node) return error_mark_node; /* Build a trivial decl-specifier-seq. */ clear_decl_specs (&decl_specs); decl_specs.type = type1; /* Call grokdeclarator to figure out what type this is. */ type1 = grokdeclarator (NULL, &decl_specs, TYPENAME, /*initialized=*/0, /*attrlist=*/NULL); if (binary) { cp_parser_require (parser, CPP_COMMA, "`,'"); type2 = cp_parser_type_id (parser); if (type2 == error_mark_node) return error_mark_node; /* Build a trivial decl-specifier-seq. */ clear_decl_specs (&decl_specs); decl_specs.type = type2; /* Call grokdeclarator to figure out what type this is. */ type2 = grokdeclarator (NULL, &decl_specs, TYPENAME, /*initialized=*/0, /*attrlist=*/NULL); } cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Complete the trait expression, which may mean either processing the trait expr now or saving it for template instantiation. */ return finish_trait_expr (kind, type1, type2); } /* Statements [gram.stmt.stmt] */ /* Parse a statement. statement: labeled-statement expression-statement compound-statement selection-statement iteration-statement jump-statement declaration-statement try-block IN_COMPOUND is true when the statement is nested inside a cp_parser_compound_statement; this matters for certain pragmas. If IF_P is not NULL, *IF_P is set to indicate whether the statement is a (possibly labeled) if statement which is not enclosed in braces and has an else clause. This is used to implement -Wparentheses. */ static void cp_parser_statement (cp_parser* parser, tree in_statement_expr, bool in_compound, bool *if_p) { tree statement; cp_token *token; location_t statement_location; restart: if (if_p != NULL) *if_p = false; /* There is no statement yet. */ statement = NULL_TREE; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Remember the location of the first token in the statement. */ statement_location = token->location; /* If this is a keyword, then that will often determine what kind of statement we have. */ if (token->type == CPP_KEYWORD) { enum rid keyword = token->keyword; switch (keyword) { case RID_CASE: case RID_DEFAULT: /* Looks like a labeled-statement with a case label. Parse the label, and then use tail recursion to parse the statement. */ cp_parser_label_for_labeled_statement (parser); goto restart; case RID_IF: case RID_SWITCH: statement = cp_parser_selection_statement (parser, if_p); break; case RID_WHILE: case RID_DO: case RID_FOR: statement = cp_parser_iteration_statement (parser); break; case RID_BREAK: case RID_CONTINUE: case RID_RETURN: case RID_GOTO: statement = cp_parser_jump_statement (parser); break; /* Objective-C++ exception-handling constructs. */ case RID_AT_TRY: case RID_AT_CATCH: case RID_AT_FINALLY: case RID_AT_SYNCHRONIZED: case RID_AT_THROW: statement = cp_parser_objc_statement (parser); break; case RID_TRY: statement = cp_parser_try_block (parser); break; case RID_NAMESPACE: /* This must be a namespace alias definition. */ cp_parser_declaration_statement (parser); return; default: /* It might be a keyword like `int' that can start a declaration-statement. */ break; } } else if (token->type == CPP_NAME) { /* If the next token is a `:', then we are looking at a labeled-statement. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); if (token->type == CPP_COLON) { /* Looks like a labeled-statement with an ordinary label. Parse the label, and then use tail recursion to parse the statement. */ cp_parser_label_for_labeled_statement (parser); goto restart; } } /* Anything that starts with a `{' must be a compound-statement. */ else if (token->type == CPP_OPEN_BRACE) statement = cp_parser_compound_statement (parser, NULL, false); /* CPP_PRAGMA is a #pragma inside a function body, which constitutes a statement all its own. */ else if (token->type == CPP_PRAGMA) { /* Only certain OpenMP pragmas are attached to statements, and thus are considered statements themselves. All others are not. In the context of a compound, accept the pragma as a "statement" and return so that we can check for a close brace. Otherwise we require a real statement and must go back and read one. */ if (in_compound) cp_parser_pragma (parser, pragma_compound); else if (!cp_parser_pragma (parser, pragma_stmt)) goto restart; return; } else if (token->type == CPP_EOF) { cp_parser_error (parser, "expected statement"); return; } /* Everything else must be a declaration-statement or an expression-statement. Try for the declaration-statement first, unless we are looking at a `;', in which case we know that we have an expression-statement. */ if (!statement) { if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { cp_parser_parse_tentatively (parser); /* Try to parse the declaration-statement. */ cp_parser_declaration_statement (parser); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return; } /* Look for an expression-statement instead. */ statement = cp_parser_expression_statement (parser, in_statement_expr); } /* Set the line number for the statement. */ if (statement && STATEMENT_CODE_P (TREE_CODE (statement))) SET_EXPR_LOCATION (statement, statement_location); } /* Parse the label for a labeled-statement, i.e. identifier : case constant-expression : default : GNU Extension: case constant-expression ... constant-expression : statement When a label is parsed without errors, the label is added to the parse tree by the finish_* functions, so this function doesn't have to return the label. */ static void cp_parser_label_for_labeled_statement (cp_parser* parser) { cp_token *token; /* The next token should be an identifier. */ token = cp_lexer_peek_token (parser->lexer); if (token->type != CPP_NAME && token->type != CPP_KEYWORD) { cp_parser_error (parser, "expected labeled-statement"); return; } switch (token->keyword) { case RID_CASE: { tree expr, expr_hi; cp_token *ellipsis; /* Consume the `case' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the constant-expression. */ expr = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, NULL); ellipsis = cp_lexer_peek_token (parser->lexer); if (ellipsis->type == CPP_ELLIPSIS) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); expr_hi = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, NULL); /* We don't need to emit warnings here, as the common code will do this for us. */ } else expr_hi = NULL_TREE; if (parser->in_switch_statement_p) finish_case_label (expr, expr_hi); else error ("case label %qE not within a switch statement", expr); } break; case RID_DEFAULT: /* Consume the `default' token. */ cp_lexer_consume_token (parser->lexer); if (parser->in_switch_statement_p) finish_case_label (NULL_TREE, NULL_TREE); else error ("case label not within a switch statement"); break; default: /* Anything else must be an ordinary label. */ finish_label_stmt (cp_parser_identifier (parser)); break; } /* Require the `:' token. */ cp_parser_require (parser, CPP_COLON, "`:'"); } /* Parse an expression-statement. expression-statement: expression [opt] ; Returns the new EXPR_STMT -- or NULL_TREE if the expression statement consists of nothing more than an `;'. IN_STATEMENT_EXPR_P indicates whether this expression-statement is part of an expression statement. */ static tree cp_parser_expression_statement (cp_parser* parser, tree in_statement_expr) { tree statement = NULL_TREE; /* If the next token is a ';', then there is no expression statement. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) statement = cp_parser_expression (parser, /*cast_p=*/false); /* Consume the final `;'. */ cp_parser_consume_semicolon_at_end_of_statement (parser); if (in_statement_expr && cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_BRACE)) /* This is the final expression statement of a statement expression. */ statement = finish_stmt_expr_expr (statement, in_statement_expr); else if (statement) statement = finish_expr_stmt (statement); else finish_stmt (); return statement; } /* Parse a compound-statement. compound-statement: { statement-seq [opt] } GNU extension: compound-statement: { label-declaration-seq [opt] statement-seq [opt] } label-declaration-seq: label-declaration label-declaration-seq label-declaration Returns a tree representing the statement. */ static tree cp_parser_compound_statement (cp_parser *parser, tree in_statement_expr, bool in_try) { tree compound_stmt; /* Consume the `{'. */ if (!cp_parser_require (parser, CPP_OPEN_BRACE, "`{'")) return error_mark_node; /* Begin the compound-statement. */ compound_stmt = begin_compound_stmt (in_try ? BCS_TRY_BLOCK : 0); /* If the next keyword is `__label__' we have a label declaration. */ while (cp_lexer_next_token_is_keyword (parser->lexer, RID_LABEL)) cp_parser_label_declaration (parser); /* Parse an (optional) statement-seq. */ cp_parser_statement_seq_opt (parser, in_statement_expr); /* Finish the compound-statement. */ finish_compound_stmt (compound_stmt); /* Consume the `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); return compound_stmt; } /* Parse an (optional) statement-seq. statement-seq: statement statement-seq [opt] statement */ static void cp_parser_statement_seq_opt (cp_parser* parser, tree in_statement_expr) { /* Scan statements until there aren't any more. */ while (true) { cp_token *token = cp_lexer_peek_token (parser->lexer); /* If we're looking at a `}', then we've run out of statements. */ if (token->type == CPP_CLOSE_BRACE || token->type == CPP_EOF || token->type == CPP_PRAGMA_EOL) break; /* If we are in a compound statement and find 'else' then something went wrong. */ else if (token->type == CPP_KEYWORD && token->keyword == RID_ELSE) { if (parser->in_statement & IN_IF_STMT) break; else { token = cp_lexer_consume_token (parser->lexer); error ("% without a previous %"); } } /* Parse the statement. */ cp_parser_statement (parser, in_statement_expr, true, NULL); } } /* Parse a selection-statement. selection-statement: if ( condition ) statement if ( condition ) statement else statement switch ( condition ) statement Returns the new IF_STMT or SWITCH_STMT. If IF_P is not NULL, *IF_P is set to indicate whether the statement is a (possibly labeled) if statement which is not enclosed in braces and has an else clause. This is used to implement -Wparentheses. */ static tree cp_parser_selection_statement (cp_parser* parser, bool *if_p) { cp_token *token; enum rid keyword; if (if_p != NULL) *if_p = false; /* Peek at the next token. */ token = cp_parser_require (parser, CPP_KEYWORD, "selection-statement"); /* See what kind of keyword it is. */ keyword = token->keyword; switch (keyword) { case RID_IF: case RID_SWITCH: { tree statement; tree condition; /* Look for the `('. */ if (!cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) { cp_parser_skip_to_end_of_statement (parser); return error_mark_node; } /* Begin the selection-statement. */ if (keyword == RID_IF) statement = begin_if_stmt (); else statement = begin_switch_stmt (); /* Parse the condition. */ condition = cp_parser_condition (parser); /* Look for the `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); if (keyword == RID_IF) { bool nested_if; unsigned char in_statement; /* Add the condition. */ finish_if_stmt_cond (condition, statement); /* Parse the then-clause. */ in_statement = parser->in_statement; parser->in_statement |= IN_IF_STMT; cp_parser_implicitly_scoped_statement (parser, &nested_if); parser->in_statement = in_statement; finish_then_clause (statement); /* If the next token is `else', parse the else-clause. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_ELSE)) { /* Consume the `else' keyword. */ cp_lexer_consume_token (parser->lexer); begin_else_clause (statement); /* Parse the else-clause. */ cp_parser_implicitly_scoped_statement (parser, NULL); finish_else_clause (statement); /* If we are currently parsing a then-clause, then IF_P will not be NULL. We set it to true to indicate that this if statement has an else clause. This may trigger the Wparentheses warning below when we get back up to the parent if statement. */ if (if_p != NULL) *if_p = true; } else { /* This if statement does not have an else clause. If NESTED_IF is true, then the then-clause is an if statement which does have an else clause. We warn about the potential ambiguity. */ if (nested_if) warning (OPT_Wparentheses, ("%Hsuggest explicit braces " "to avoid ambiguous %"), EXPR_LOCUS (statement)); } /* Now we're all done with the if-statement. */ finish_if_stmt (statement); } else { bool in_switch_statement_p; unsigned char in_statement; /* Add the condition. */ finish_switch_cond (condition, statement); /* Parse the body of the switch-statement. */ in_switch_statement_p = parser->in_switch_statement_p; in_statement = parser->in_statement; parser->in_switch_statement_p = true; parser->in_statement |= IN_SWITCH_STMT; cp_parser_implicitly_scoped_statement (parser, NULL); parser->in_switch_statement_p = in_switch_statement_p; parser->in_statement = in_statement; /* Now we're all done with the switch-statement. */ finish_switch_stmt (statement); } return statement; } break; default: cp_parser_error (parser, "expected selection-statement"); return error_mark_node; } } /* Parse a condition. condition: expression type-specifier-seq declarator = assignment-expression GNU Extension: condition: type-specifier-seq declarator asm-specification [opt] attributes [opt] = assignment-expression Returns the expression that should be tested. */ static tree cp_parser_condition (cp_parser* parser) { cp_decl_specifier_seq type_specifiers; const char *saved_message; /* Try the declaration first. */ cp_parser_parse_tentatively (parser); /* New types are not allowed in the type-specifier-seq for a condition. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in conditions"; /* Parse the type-specifier-seq. */ cp_parser_type_specifier_seq (parser, /*is_condition==*/true, &type_specifiers); /* Restore the saved message. */ parser->type_definition_forbidden_message = saved_message; /* If all is well, we might be looking at a declaration. */ if (!cp_parser_error_occurred (parser)) { tree decl; tree asm_specification; tree attributes; cp_declarator *declarator; tree initializer = NULL_TREE; /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL, /*member_p=*/false); /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); /* Parse the asm-specification. */ asm_specification = cp_parser_asm_specification_opt (parser); /* If the next token is not an `=', then we might still be looking at an expression. For example: if (A(a).x) looks like a decl-specifier-seq and a declarator -- but then there is no `=', so this is an expression. */ cp_parser_require (parser, CPP_EQ, "`='"); /* If we did see an `=', then we are looking at a declaration for sure. */ if (cp_parser_parse_definitely (parser)) { tree pushed_scope; bool non_constant_p; /* Create the declaration. */ decl = start_decl (declarator, &type_specifiers, /*initialized_p=*/true, attributes, /*prefix_attributes=*/NULL_TREE, &pushed_scope); /* Parse the assignment-expression. */ initializer = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/true, &non_constant_p); if (!non_constant_p) initializer = fold_non_dependent_expr (initializer); /* Process the initializer. */ cp_finish_decl (decl, initializer, !non_constant_p, asm_specification, LOOKUP_ONLYCONVERTING); if (pushed_scope) pop_scope (pushed_scope); return convert_from_reference (decl); } } /* If we didn't even get past the declarator successfully, we are definitely not looking at a declaration. */ else cp_parser_abort_tentative_parse (parser); /* Otherwise, we are looking at an expression. */ return cp_parser_expression (parser, /*cast_p=*/false); } /* We check for a ) immediately followed by ; with no whitespacing between. This is used to issue a warning for: while (...); and: for (...); as the semicolon is probably extraneous. On parse errors, the next token might not be a ), so do nothing in that case. */ static void check_empty_body (cp_parser* parser, const char* type) { cp_token *token; cp_token *close_paren; expanded_location close_loc; expanded_location semi_loc; close_paren = cp_lexer_peek_token (parser->lexer); if (close_paren->type != CPP_CLOSE_PAREN) return; close_loc = expand_location (close_paren->location); token = cp_lexer_peek_nth_token (parser->lexer, 2); if (token->type != CPP_SEMICOLON || (token->flags & PREV_WHITE)) return; semi_loc = expand_location (token->location); if (close_loc.line == semi_loc.line && close_loc.column+1 == semi_loc.column) warning (OPT_Wempty_body, "suggest a space before %<;%> or explicit braces around empty " "body in %<%s%> statement", type); } /* Parse an iteration-statement. iteration-statement: while ( condition ) statement do statement while ( expression ) ; for ( for-init-statement condition [opt] ; expression [opt] ) statement Returns the new WHILE_STMT, DO_STMT, or FOR_STMT. */ static tree cp_parser_iteration_statement (cp_parser* parser) { cp_token *token; enum rid keyword; tree statement; unsigned char in_statement; /* Peek at the next token. */ token = cp_parser_require (parser, CPP_KEYWORD, "iteration-statement"); if (!token) return error_mark_node; /* Remember whether or not we are already within an iteration statement. */ in_statement = parser->in_statement; /* See what kind of keyword it is. */ keyword = token->keyword; switch (keyword) { case RID_WHILE: { tree condition; /* Begin the while-statement. */ statement = begin_while_stmt (); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the condition. */ condition = cp_parser_condition (parser); finish_while_stmt_cond (condition, statement); check_empty_body (parser, "while"); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Parse the dependent statement. */ parser->in_statement = IN_ITERATION_STMT; cp_parser_already_scoped_statement (parser); parser->in_statement = in_statement; /* We're done with the while-statement. */ finish_while_stmt (statement); } break; case RID_DO: { tree expression; /* Begin the do-statement. */ statement = begin_do_stmt (); /* Parse the body of the do-statement. */ parser->in_statement = IN_ITERATION_STMT; cp_parser_implicitly_scoped_statement (parser, NULL); parser->in_statement = in_statement; finish_do_body (statement); /* Look for the `while' keyword. */ cp_parser_require_keyword (parser, RID_WHILE, "`while'"); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the expression. */ expression = cp_parser_expression (parser, /*cast_p=*/false); /* We're done with the do-statement. */ finish_do_stmt (expression, statement); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Look for the `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } break; case RID_FOR: { tree condition = NULL_TREE; tree expression = NULL_TREE; /* Begin the for-statement. */ statement = begin_for_stmt (); /* Look for the `('. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the initialization. */ cp_parser_for_init_statement (parser); finish_for_init_stmt (statement); /* If there's a condition, process it. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) condition = cp_parser_condition (parser); finish_for_cond (condition, statement); /* Look for the `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); /* If there's an expression, process it. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) expression = cp_parser_expression (parser, /*cast_p=*/false); finish_for_expr (expression, statement); check_empty_body (parser, "for"); /* Look for the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Parse the body of the for-statement. */ parser->in_statement = IN_ITERATION_STMT; cp_parser_already_scoped_statement (parser); parser->in_statement = in_statement; /* We're done with the for-statement. */ finish_for_stmt (statement); } break; default: cp_parser_error (parser, "expected iteration-statement"); statement = error_mark_node; break; } return statement; } /* Parse a for-init-statement. for-init-statement: expression-statement simple-declaration */ static void cp_parser_for_init_statement (cp_parser* parser) { /* If the next token is a `;', then we have an empty expression-statement. Grammatically, this is also a simple-declaration, but an invalid one, because it does not declare anything. Therefore, if we did not handle this case specially, we would issue an error message about an invalid declaration. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { /* We're going to speculatively look for a declaration, falling back to an expression, if necessary. */ cp_parser_parse_tentatively (parser); /* Parse the declaration. */ cp_parser_simple_declaration (parser, /*function_definition_allowed_p=*/false); /* If the tentative parse failed, then we shall need to look for an expression-statement. */ if (cp_parser_parse_definitely (parser)) return; } cp_parser_expression_statement (parser, false); } /* Parse a jump-statement. jump-statement: break ; continue ; return expression [opt] ; goto identifier ; GNU extension: jump-statement: goto * expression ; Returns the new BREAK_STMT, CONTINUE_STMT, RETURN_EXPR, or GOTO_EXPR. */ static tree cp_parser_jump_statement (cp_parser* parser) { tree statement = error_mark_node; cp_token *token; enum rid keyword; unsigned char in_statement; /* Peek at the next token. */ token = cp_parser_require (parser, CPP_KEYWORD, "jump-statement"); if (!token) return error_mark_node; /* See what kind of keyword it is. */ keyword = token->keyword; switch (keyword) { case RID_BREAK: in_statement = parser->in_statement & ~IN_IF_STMT; switch (in_statement) { case 0: error ("break statement not within loop or switch"); break; default: gcc_assert ((in_statement & IN_SWITCH_STMT) || in_statement == IN_ITERATION_STMT); statement = finish_break_stmt (); break; case IN_OMP_BLOCK: error ("invalid exit from OpenMP structured block"); break; case IN_OMP_FOR: error ("break statement used with OpenMP for loop"); break; } cp_parser_require (parser, CPP_SEMICOLON, "%<;%>"); break; case RID_CONTINUE: switch (parser->in_statement & ~(IN_SWITCH_STMT | IN_IF_STMT)) { case 0: error ("continue statement not within a loop"); break; case IN_ITERATION_STMT: case IN_OMP_FOR: statement = finish_continue_stmt (); break; case IN_OMP_BLOCK: error ("invalid exit from OpenMP structured block"); break; default: gcc_unreachable (); } cp_parser_require (parser, CPP_SEMICOLON, "%<;%>"); break; case RID_RETURN: { tree expr; /* If the next token is a `;', then there is no expression. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) expr = cp_parser_expression (parser, /*cast_p=*/false); else expr = NULL_TREE; /* Build the return-statement. */ statement = finish_return_stmt (expr); /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "%<;%>"); } break; case RID_GOTO: /* Create the goto-statement. */ if (cp_lexer_next_token_is (parser->lexer, CPP_MULT)) { /* Issue a warning about this use of a GNU extension. */ if (pedantic) pedwarn ("ISO C++ forbids computed gotos"); /* Consume the '*' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the dependent expression. */ finish_goto_stmt (cp_parser_expression (parser, /*cast_p=*/false)); } else finish_goto_stmt (cp_parser_identifier (parser)); /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "%<;%>"); break; default: cp_parser_error (parser, "expected jump-statement"); break; } return statement; } /* Parse a declaration-statement. declaration-statement: block-declaration */ static void cp_parser_declaration_statement (cp_parser* parser) { void *p; /* Get the high-water mark for the DECLARATOR_OBSTACK. */ p = obstack_alloc (&declarator_obstack, 0); /* Parse the block-declaration. */ cp_parser_block_declaration (parser, /*statement_p=*/true); /* Free any declarators allocated. */ obstack_free (&declarator_obstack, p); /* Finish off the statement. */ finish_stmt (); } /* Some dependent statements (like `if (cond) statement'), are implicitly in their own scope. In other words, if the statement is a single statement (as opposed to a compound-statement), it is none-the-less treated as if it were enclosed in braces. Any declarations appearing in the dependent statement are out of scope after control passes that point. This function parses a statement, but ensures that is in its own scope, even if it is not a compound-statement. If IF_P is not NULL, *IF_P is set to indicate whether the statement is a (possibly labeled) if statement which is not enclosed in braces and has an else clause. This is used to implement -Wparentheses. Returns the new statement. */ static tree cp_parser_implicitly_scoped_statement (cp_parser* parser, bool *if_p) { tree statement; if (if_p != NULL) *if_p = false; /* Mark if () ; with a special NOP_EXPR. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) { cp_lexer_consume_token (parser->lexer); statement = add_stmt (build_empty_stmt ()); } /* if a compound is opened, we simply parse the statement directly. */ else if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) statement = cp_parser_compound_statement (parser, NULL, false); /* If the token is not a `{', then we must take special action. */ else { /* Create a compound-statement. */ statement = begin_compound_stmt (0); /* Parse the dependent-statement. */ cp_parser_statement (parser, NULL_TREE, false, if_p); /* Finish the dummy compound-statement. */ finish_compound_stmt (statement); } /* Return the statement. */ return statement; } /* For some dependent statements (like `while (cond) statement'), we have already created a scope. Therefore, even if the dependent statement is a compound-statement, we do not want to create another scope. */ static void cp_parser_already_scoped_statement (cp_parser* parser) { /* If the token is a `{', then we must take special action. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_BRACE)) cp_parser_statement (parser, NULL_TREE, false, NULL); else { /* Avoid calling cp_parser_compound_statement, so that we don't create a new scope. Do everything else by hand. */ cp_parser_require (parser, CPP_OPEN_BRACE, "`{'"); cp_parser_statement_seq_opt (parser, NULL_TREE); cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } } /* Declarations [gram.dcl.dcl] */ /* Parse an optional declaration-sequence. declaration-seq: declaration declaration-seq declaration */ static void cp_parser_declaration_seq_opt (cp_parser* parser) { while (true) { cp_token *token; token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_CLOSE_BRACE || token->type == CPP_EOF || token->type == CPP_PRAGMA_EOL) break; if (token->type == CPP_SEMICOLON) { /* A declaration consisting of a single semicolon is invalid. Allow it unless we're being pedantic. */ cp_lexer_consume_token (parser->lexer); if (pedantic && !in_system_header) pedwarn ("extra %<;%>"); continue; } /* If we're entering or exiting a region that's implicitly extern "C", modify the lang context appropriately. */ if (!parser->implicit_extern_c && token->implicit_extern_c) { push_lang_context (lang_name_c); parser->implicit_extern_c = true; } else if (parser->implicit_extern_c && !token->implicit_extern_c) { pop_lang_context (); parser->implicit_extern_c = false; } if (token->type == CPP_PRAGMA) { /* A top-level declaration can consist solely of a #pragma. A nested declaration cannot, so this is done here and not in cp_parser_declaration. (A #pragma at block scope is handled in cp_parser_statement.) */ cp_parser_pragma (parser, pragma_external); continue; } /* Parse the declaration itself. */ cp_parser_declaration (parser); } } /* Parse a declaration. declaration: block-declaration function-definition template-declaration explicit-instantiation explicit-specialization linkage-specification namespace-definition GNU extension: declaration: __extension__ declaration */ static void cp_parser_declaration (cp_parser* parser) { cp_token token1; cp_token token2; int saved_pedantic; void *p; /* Check for the `__extension__' keyword. */ if (cp_parser_extension_opt (parser, &saved_pedantic)) { /* Parse the qualified declaration. */ cp_parser_declaration (parser); /* Restore the PEDANTIC flag. */ pedantic = saved_pedantic; return; } /* Try to figure out what kind of declaration is present. */ token1 = *cp_lexer_peek_token (parser->lexer); if (token1.type != CPP_EOF) token2 = *cp_lexer_peek_nth_token (parser->lexer, 2); else { token2.type = CPP_EOF; token2.keyword = RID_MAX; } /* Get the high-water mark for the DECLARATOR_OBSTACK. */ p = obstack_alloc (&declarator_obstack, 0); /* If the next token is `extern' and the following token is a string literal, then we have a linkage specification. */ if (token1.keyword == RID_EXTERN && cp_parser_is_string_literal (&token2)) cp_parser_linkage_specification (parser); /* If the next token is `template', then we have either a template declaration, an explicit instantiation, or an explicit specialization. */ else if (token1.keyword == RID_TEMPLATE) { /* `template <>' indicates a template specialization. */ if (token2.type == CPP_LESS && cp_lexer_peek_nth_token (parser->lexer, 3)->type == CPP_GREATER) cp_parser_explicit_specialization (parser); /* `template <' indicates a template declaration. */ else if (token2.type == CPP_LESS) cp_parser_template_declaration (parser, /*member_p=*/false); /* Anything else must be an explicit instantiation. */ else cp_parser_explicit_instantiation (parser); } /* If the next token is `export', then we have a template declaration. */ else if (token1.keyword == RID_EXPORT) cp_parser_template_declaration (parser, /*member_p=*/false); /* If the next token is `extern', 'static' or 'inline' and the one after that is `template', we have a GNU extended explicit instantiation directive. */ else if (cp_parser_allow_gnu_extensions_p (parser) && (token1.keyword == RID_EXTERN || token1.keyword == RID_STATIC || token1.keyword == RID_INLINE) && token2.keyword == RID_TEMPLATE) cp_parser_explicit_instantiation (parser); /* If the next token is `namespace', check for a named or unnamed namespace definition. */ else if (token1.keyword == RID_NAMESPACE && (/* A named namespace definition. */ (token2.type == CPP_NAME && (cp_lexer_peek_nth_token (parser->lexer, 3)->type != CPP_EQ)) /* An unnamed namespace definition. */ || token2.type == CPP_OPEN_BRACE || token2.keyword == RID_ATTRIBUTE)) cp_parser_namespace_definition (parser); /* An inline (associated) namespace definition. */ else if (token1.keyword == RID_INLINE && token2.keyword == RID_NAMESPACE) cp_parser_namespace_definition (parser); /* Objective-C++ declaration/definition. */ else if (c_dialect_objc () && OBJC_IS_AT_KEYWORD (token1.keyword)) cp_parser_objc_declaration (parser); /* We must have either a block declaration or a function definition. */ else /* Try to parse a block-declaration, or a function-definition. */ cp_parser_block_declaration (parser, /*statement_p=*/false); /* Free any declarators allocated. */ obstack_free (&declarator_obstack, p); } /* Parse a block-declaration. block-declaration: simple-declaration asm-definition namespace-alias-definition using-declaration using-directive GNU Extension: block-declaration: __extension__ block-declaration C++0x Extension: block-declaration: static_assert-declaration If STATEMENT_P is TRUE, then this block-declaration is occurring as part of a declaration-statement. */ static void cp_parser_block_declaration (cp_parser *parser, bool statement_p) { cp_token *token1; int saved_pedantic; /* Check for the `__extension__' keyword. */ if (cp_parser_extension_opt (parser, &saved_pedantic)) { /* Parse the qualified declaration. */ cp_parser_block_declaration (parser, statement_p); /* Restore the PEDANTIC flag. */ pedantic = saved_pedantic; return; } /* Peek at the next token to figure out which kind of declaration is present. */ token1 = cp_lexer_peek_token (parser->lexer); /* If the next keyword is `asm', we have an asm-definition. */ if (token1->keyword == RID_ASM) { if (statement_p) cp_parser_commit_to_tentative_parse (parser); cp_parser_asm_definition (parser); } /* If the next keyword is `namespace', we have a namespace-alias-definition. */ else if (token1->keyword == RID_NAMESPACE) cp_parser_namespace_alias_definition (parser); /* If the next keyword is `using', we have either a using-declaration or a using-directive. */ else if (token1->keyword == RID_USING) { cp_token *token2; if (statement_p) cp_parser_commit_to_tentative_parse (parser); /* If the token after `using' is `namespace', then we have a using-directive. */ token2 = cp_lexer_peek_nth_token (parser->lexer, 2); if (token2->keyword == RID_NAMESPACE) cp_parser_using_directive (parser); /* Otherwise, it's a using-declaration. */ else cp_parser_using_declaration (parser, /*access_declaration_p=*/false); } /* If the next keyword is `__label__' we have a misplaced label declaration. */ else if (token1->keyword == RID_LABEL) { cp_lexer_consume_token (parser->lexer); error ("%<__label__%> not at the beginning of a block"); cp_parser_skip_to_end_of_statement (parser); /* If the next token is now a `;', consume it. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) cp_lexer_consume_token (parser->lexer); } /* If the next token is `static_assert' we have a static assertion. */ else if (token1->keyword == RID_STATIC_ASSERT) cp_parser_static_assert (parser, /*member_p=*/false); /* Anything else must be a simple-declaration. */ else cp_parser_simple_declaration (parser, !statement_p); } /* Parse a simple-declaration. simple-declaration: decl-specifier-seq [opt] init-declarator-list [opt] ; init-declarator-list: init-declarator init-declarator-list , init-declarator If FUNCTION_DEFINITION_ALLOWED_P is TRUE, then we also recognize a function-definition as a simple-declaration. */ static void cp_parser_simple_declaration (cp_parser* parser, bool function_definition_allowed_p) { cp_decl_specifier_seq decl_specifiers; int declares_class_or_enum; bool saw_declarator; /* Defer access checks until we know what is being declared; the checks for names appearing in the decl-specifier-seq should be done as if we were in the scope of the thing being declared. */ push_deferring_access_checks (dk_deferred); /* Parse the decl-specifier-seq. We have to keep track of whether or not the decl-specifier-seq declares a named class or enumeration type, since that is the only case in which the init-declarator-list is allowed to be empty. [dcl.dcl] In a simple-declaration, the optional init-declarator-list can be omitted only when declaring a class or enumeration, that is when the decl-specifier-seq contains either a class-specifier, an elaborated-type-specifier, or an enum-specifier. */ cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_OPTIONAL, &decl_specifiers, &declares_class_or_enum); /* We no longer need to defer access checks. */ stop_deferring_access_checks (); /* In a block scope, a valid declaration must always have a decl-specifier-seq. By not trying to parse declarators, we can resolve the declaration/expression ambiguity more quickly. */ if (!function_definition_allowed_p && !decl_specifiers.any_specifiers_p) { cp_parser_error (parser, "expected declaration"); goto done; } /* If the next two tokens are both identifiers, the code is erroneous. The usual cause of this situation is code like: T t; where "T" should name a type -- but does not. */ if (!decl_specifiers.type && cp_parser_parse_and_diagnose_invalid_type_name (parser)) { /* If parsing tentatively, we should commit; we really are looking at a declaration. */ cp_parser_commit_to_tentative_parse (parser); /* Give up. */ goto done; } /* If we have seen at least one decl-specifier, and the next token is not a parenthesis, then we must be looking at a declaration. (After "int (" we might be looking at a functional cast.) */ if (decl_specifiers.any_specifiers_p && cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_PAREN)) cp_parser_commit_to_tentative_parse (parser); /* Keep going until we hit the `;' at the end of the simple declaration. */ saw_declarator = false; while (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) { cp_token *token; bool function_definition_p; tree decl; if (saw_declarator) { /* If we are processing next declarator, coma is expected */ token = cp_lexer_peek_token (parser->lexer); gcc_assert (token->type == CPP_COMMA); cp_lexer_consume_token (parser->lexer); } else saw_declarator = true; /* Parse the init-declarator. */ decl = cp_parser_init_declarator (parser, &decl_specifiers, /*checks=*/NULL, function_definition_allowed_p, /*member_p=*/false, declares_class_or_enum, &function_definition_p); /* If an error occurred while parsing tentatively, exit quickly. (That usually happens when in the body of a function; each statement is treated as a declaration-statement until proven otherwise.) */ if (cp_parser_error_occurred (parser)) goto done; /* Handle function definitions specially. */ if (function_definition_p) { /* If the next token is a `,', then we are probably processing something like: void f() {}, *p; which is erroneous. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) error ("mixing declarations and function-definitions is forbidden"); /* Otherwise, we're done with the list of declarators. */ else { pop_deferring_access_checks (); return; } } /* The next token should be either a `,' or a `;'. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `,', there are more declarators to come. */ if (token->type == CPP_COMMA) /* will be consumed next time around */; /* If it's a `;', we are done. */ else if (token->type == CPP_SEMICOLON) break; /* Anything else is an error. */ else { /* If we have already issued an error message we don't need to issue another one. */ if (decl != error_mark_node || cp_parser_uncommitted_to_tentative_parse_p (parser)) cp_parser_error (parser, "expected %<,%> or %<;%>"); /* Skip tokens until we reach the end of the statement. */ cp_parser_skip_to_end_of_statement (parser); /* If the next token is now a `;', consume it. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) cp_lexer_consume_token (parser->lexer); goto done; } /* After the first time around, a function-definition is not allowed -- even if it was OK at first. For example: int i, f() {} is not valid. */ function_definition_allowed_p = false; } /* Issue an error message if no declarators are present, and the decl-specifier-seq does not itself declare a class or enumeration. */ if (!saw_declarator) { if (cp_parser_declares_only_class_p (parser)) shadow_tag (&decl_specifiers); /* Perform any deferred access checks. */ perform_deferred_access_checks (); } /* Consume the `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); done: pop_deferring_access_checks (); } /* Parse a decl-specifier-seq. decl-specifier-seq: decl-specifier-seq [opt] decl-specifier decl-specifier: storage-class-specifier type-specifier function-specifier friend typedef GNU Extension: decl-specifier: attributes Set *DECL_SPECS to a representation of the decl-specifier-seq. The parser flags FLAGS is used to control type-specifier parsing. *DECLARES_CLASS_OR_ENUM is set to the bitwise or of the following flags: 1: one of the decl-specifiers is an elaborated-type-specifier (i.e., a type declaration) 2: one of the decl-specifiers is an enum-specifier or a class-specifier (i.e., a type definition) */ static void cp_parser_decl_specifier_seq (cp_parser* parser, cp_parser_flags flags, cp_decl_specifier_seq *decl_specs, int* declares_class_or_enum) { bool constructor_possible_p = !parser->in_declarator_p; /* Clear DECL_SPECS. */ clear_decl_specs (decl_specs); /* Assume no class or enumeration type is declared. */ *declares_class_or_enum = 0; /* Keep reading specifiers until there are no more to read. */ while (true) { bool constructor_p; bool found_decl_spec; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Handle attributes. */ if (token->keyword == RID_ATTRIBUTE) { /* Parse the attributes. */ decl_specs->attributes = chainon (decl_specs->attributes, cp_parser_attributes_opt (parser)); continue; } /* Assume we will find a decl-specifier keyword. */ found_decl_spec = true; /* If the next token is an appropriate keyword, we can simply add it to the list. */ switch (token->keyword) { /* decl-specifier: friend */ case RID_FRIEND: if (!at_class_scope_p ()) { error ("%H% used outside of class", &token->location); cp_lexer_purge_token (parser->lexer); } else { ++decl_specs->specs[(int) ds_friend]; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } break; /* function-specifier: inline virtual explicit */ case RID_INLINE: case RID_VIRTUAL: case RID_EXPLICIT: cp_parser_function_specifier_opt (parser, decl_specs); break; /* decl-specifier: typedef */ case RID_TYPEDEF: ++decl_specs->specs[(int) ds_typedef]; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); /* A constructor declarator cannot appear in a typedef. */ constructor_possible_p = false; /* The "typedef" keyword can only occur in a declaration; we may as well commit at this point. */ cp_parser_commit_to_tentative_parse (parser); if (decl_specs->storage_class != sc_none) decl_specs->conflicting_specifiers_p = true; break; /* storage-class-specifier: auto register static extern mutable GNU Extension: thread */ case RID_AUTO: /* Consume the token. */ cp_lexer_consume_token (parser->lexer); if (cxx_dialect == cxx98) { /* Complain about `auto' as a storage specifier, if we're complaining about C++0x compatibility. */ warning (OPT_Wc__0x_compat, "% will change meaning in C++0x; please remove it"); /* Set the storage class anyway. */ cp_parser_set_storage_class (parser, decl_specs, RID_AUTO); } else /* We do not yet support the use of `auto' as a type-specifier. */ error ("C++0x % specifier not supported"); break; case RID_REGISTER: case RID_STATIC: case RID_EXTERN: case RID_MUTABLE: /* Consume the token. */ cp_lexer_consume_token (parser->lexer); cp_parser_set_storage_class (parser, decl_specs, token->keyword); break; case RID_THREAD: /* Consume the token. */ cp_lexer_consume_token (parser->lexer); ++decl_specs->specs[(int) ds_thread]; break; default: /* We did not yet find a decl-specifier yet. */ found_decl_spec = false; break; } /* Constructors are a special case. The `S' in `S()' is not a decl-specifier; it is the beginning of the declarator. */ constructor_p = (!found_decl_spec && constructor_possible_p && (cp_parser_constructor_declarator_p (parser, decl_specs->specs[(int) ds_friend] != 0))); /* If we don't have a DECL_SPEC yet, then we must be looking at a type-specifier. */ if (!found_decl_spec && !constructor_p) { int decl_spec_declares_class_or_enum; bool is_cv_qualifier; tree type_spec; type_spec = cp_parser_type_specifier (parser, flags, decl_specs, /*is_declaration=*/true, &decl_spec_declares_class_or_enum, &is_cv_qualifier); *declares_class_or_enum |= decl_spec_declares_class_or_enum; /* If this type-specifier referenced a user-defined type (a typedef, class-name, etc.), then we can't allow any more such type-specifiers henceforth. [dcl.spec] The longest sequence of decl-specifiers that could possibly be a type name is taken as the decl-specifier-seq of a declaration. The sequence shall be self-consistent as described below. [dcl.type] As a general rule, at most one type-specifier is allowed in the complete decl-specifier-seq of a declaration. The only exceptions are the following: -- const or volatile can be combined with any other type-specifier. -- signed or unsigned can be combined with char, long, short, or int. -- .. Example: typedef char* Pc; void g (const int Pc); Here, Pc is *not* part of the decl-specifier seq; it's the declarator. Therefore, once we see a type-specifier (other than a cv-qualifier), we forbid any additional user-defined types. We *do* still allow things like `int int' to be considered a decl-specifier-seq, and issue the error message later. */ if (type_spec && !is_cv_qualifier) flags |= CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES; /* A constructor declarator cannot follow a type-specifier. */ if (type_spec) { constructor_possible_p = false; found_decl_spec = true; } } /* If we still do not have a DECL_SPEC, then there are no more decl-specifiers. */ if (!found_decl_spec) break; decl_specs->any_specifiers_p = true; /* After we see one decl-specifier, further decl-specifiers are always optional. */ flags |= CP_PARSER_FLAGS_OPTIONAL; } cp_parser_check_decl_spec (decl_specs); /* Don't allow a friend specifier with a class definition. */ if (decl_specs->specs[(int) ds_friend] != 0 && (*declares_class_or_enum & 2)) error ("class definition may not be declared a friend"); } /* Parse an (optional) storage-class-specifier. storage-class-specifier: auto register static extern mutable GNU Extension: storage-class-specifier: thread Returns an IDENTIFIER_NODE corresponding to the keyword used. */ static tree cp_parser_storage_class_specifier_opt (cp_parser* parser) { switch (cp_lexer_peek_token (parser->lexer)->keyword) { case RID_AUTO: if (cxx_dialect != cxx98) return NULL_TREE; /* Fall through for C++98. */ case RID_REGISTER: case RID_STATIC: case RID_EXTERN: case RID_MUTABLE: case RID_THREAD: /* Consume the token. */ return cp_lexer_consume_token (parser->lexer)->u.value; default: return NULL_TREE; } } /* Parse an (optional) function-specifier. function-specifier: inline virtual explicit Returns an IDENTIFIER_NODE corresponding to the keyword used. Updates DECL_SPECS, if it is non-NULL. */ static tree cp_parser_function_specifier_opt (cp_parser* parser, cp_decl_specifier_seq *decl_specs) { switch (cp_lexer_peek_token (parser->lexer)->keyword) { case RID_INLINE: if (decl_specs) ++decl_specs->specs[(int) ds_inline]; break; case RID_VIRTUAL: /* 14.5.2.3 [temp.mem] A member function template shall not be virtual. */ if (PROCESSING_REAL_TEMPLATE_DECL_P ()) error ("templates may not be %"); else if (decl_specs) ++decl_specs->specs[(int) ds_virtual]; break; case RID_EXPLICIT: if (decl_specs) ++decl_specs->specs[(int) ds_explicit]; break; default: return NULL_TREE; } /* Consume the token. */ return cp_lexer_consume_token (parser->lexer)->u.value; } /* Parse a linkage-specification. linkage-specification: extern string-literal { declaration-seq [opt] } extern string-literal declaration */ static void cp_parser_linkage_specification (cp_parser* parser) { tree linkage; /* Look for the `extern' keyword. */ cp_parser_require_keyword (parser, RID_EXTERN, "`extern'"); /* Look for the string-literal. */ linkage = cp_parser_string_literal (parser, false, false); /* Transform the literal into an identifier. If the literal is a wide-character string, or contains embedded NULs, then we can't handle it as the user wants. */ if (strlen (TREE_STRING_POINTER (linkage)) != (size_t) (TREE_STRING_LENGTH (linkage) - 1)) { cp_parser_error (parser, "invalid linkage-specification"); /* Assume C++ linkage. */ linkage = lang_name_cplusplus; } else linkage = get_identifier (TREE_STRING_POINTER (linkage)); /* We're now using the new linkage. */ push_lang_context (linkage); /* If the next token is a `{', then we're using the first production. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) { /* Consume the `{' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the declarations. */ cp_parser_declaration_seq_opt (parser); /* Look for the closing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } /* Otherwise, there's just one declaration. */ else { bool saved_in_unbraced_linkage_specification_p; saved_in_unbraced_linkage_specification_p = parser->in_unbraced_linkage_specification_p; parser->in_unbraced_linkage_specification_p = true; cp_parser_declaration (parser); parser->in_unbraced_linkage_specification_p = saved_in_unbraced_linkage_specification_p; } /* We're done with the linkage-specification. */ pop_lang_context (); } /* Parse a static_assert-declaration. static_assert-declaration: static_assert ( constant-expression , string-literal ) ; If MEMBER_P, this static_assert is a class member. */ static void cp_parser_static_assert(cp_parser *parser, bool member_p) { tree condition; tree message; cp_token *token; location_t saved_loc; /* Peek at the `static_assert' token so we can keep track of exactly where the static assertion started. */ token = cp_lexer_peek_token (parser->lexer); saved_loc = token->location; /* Look for the `static_assert' keyword. */ if (!cp_parser_require_keyword (parser, RID_STATIC_ASSERT, "`static_assert'")) return; /* We know we are in a static assertion; commit to any tentative parse. */ if (cp_parser_parsing_tentatively (parser)) cp_parser_commit_to_tentative_parse (parser); /* Parse the `(' starting the static assertion condition. */ cp_parser_require (parser, CPP_OPEN_PAREN, "`('"); /* Parse the constant-expression. */ condition = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, /*non_constant_p=*/NULL); /* Parse the separating `,'. */ cp_parser_require (parser, CPP_COMMA, "`,'"); /* Parse the string-literal message. */ message = cp_parser_string_literal (parser, /*translate=*/false, /*wide_ok=*/true); /* A `)' completes the static assertion. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/false, /*consume_paren=*/true); /* A semicolon terminates the declaration. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); /* Complete the static assertion, which may mean either processing the static assert now or saving it for template instantiation. */ finish_static_assert (condition, message, saved_loc, member_p); } /* Parse a `decltype' type. Returns the type. simple-type-specifier: decltype ( expression ) */ static tree cp_parser_decltype (cp_parser *parser) { tree expr; bool id_expression_or_member_access_p = false; const char *saved_message; bool saved_integral_constant_expression_p; bool saved_non_integral_constant_expression_p; /* Look for the `decltype' token. */ if (!cp_parser_require_keyword (parser, RID_DECLTYPE, "`decltype'")) return error_mark_node; /* Types cannot be defined in a `decltype' expression. Save away the old message. */ saved_message = parser->type_definition_forbidden_message; /* And create the new one. */ parser->type_definition_forbidden_message = "types may not be defined in `decltype' expressions"; /* The restrictions on constant-expressions do not apply inside decltype expressions. */ saved_integral_constant_expression_p = parser->integral_constant_expression_p; saved_non_integral_constant_expression_p = parser->non_integral_constant_expression_p; parser->integral_constant_expression_p = false; /* Do not actually evaluate the expression. */ ++skip_evaluation; /* Parse the opening `('. */ if (!cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) return error_mark_node; /* First, try parsing an id-expression. */ cp_parser_parse_tentatively (parser); expr = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*template_p=*/NULL, /*declarator_p=*/false, /*optional_p=*/false); if (!cp_parser_error_occurred (parser) && expr != error_mark_node) { bool non_integral_constant_expression_p = false; tree id_expression = expr; cp_id_kind idk; const char *error_msg; if (TREE_CODE (expr) == IDENTIFIER_NODE) /* Lookup the name we got back from the id-expression. */ expr = cp_parser_lookup_name (parser, expr, none_type, /*is_template=*/false, /*is_namespace=*/false, /*check_dependency=*/true, /*ambiguous_decls=*/NULL); if (expr && expr != error_mark_node && TREE_CODE (expr) != TEMPLATE_ID_EXPR && TREE_CODE (expr) != TYPE_DECL && (TREE_CODE (expr) != BIT_NOT_EXPR || !TYPE_P (TREE_OPERAND (expr, 0))) && cp_lexer_peek_token (parser->lexer)->type == CPP_CLOSE_PAREN) { /* Complete lookup of the id-expression. */ expr = (finish_id_expression (id_expression, expr, parser->scope, &idk, /*integral_constant_expression_p=*/false, /*allow_non_integral_constant_expression_p=*/true, &non_integral_constant_expression_p, /*template_p=*/false, /*done=*/true, /*address_p=*/false, /*template_arg_p=*/false, &error_msg)); if (expr == error_mark_node) /* We found an id-expression, but it was something that we should not have found. This is an error, not something we can recover from, so note that we found an id-expression and we'll recover as gracefully as possible. */ id_expression_or_member_access_p = true; } if (expr && expr != error_mark_node && cp_lexer_peek_token (parser->lexer)->type == CPP_CLOSE_PAREN) /* We have an id-expression. */ id_expression_or_member_access_p = true; } if (!id_expression_or_member_access_p) { /* Abort the id-expression parse. */ cp_parser_abort_tentative_parse (parser); /* Parsing tentatively, again. */ cp_parser_parse_tentatively (parser); /* Parse a class member access. */ expr = cp_parser_postfix_expression (parser, /*address_p=*/false, /*cast_p=*/false, /*member_access_only_p=*/true); if (expr && expr != error_mark_node && cp_lexer_peek_token (parser->lexer)->type == CPP_CLOSE_PAREN) /* We have an id-expression. */ id_expression_or_member_access_p = true; } if (id_expression_or_member_access_p) /* We have parsed the complete id-expression or member access. */ cp_parser_parse_definitely (parser); else { /* Abort our attempt to parse an id-expression or member access expression. */ cp_parser_abort_tentative_parse (parser); /* Parse a full expression. */ expr = cp_parser_expression (parser, /*cast_p=*/false); } /* Go back to evaluating expressions. */ --skip_evaluation; /* Restore the old message and the integral constant expression flags. */ parser->type_definition_forbidden_message = saved_message; parser->integral_constant_expression_p = saved_integral_constant_expression_p; parser->non_integral_constant_expression_p = saved_non_integral_constant_expression_p; if (expr == error_mark_node) { /* Skip everything up to the closing `)'. */ cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); return error_mark_node; } /* Parse to the closing `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) { cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); return error_mark_node; } return finish_decltype_type (expr, id_expression_or_member_access_p); } /* Special member functions [gram.special] */ /* Parse a conversion-function-id. conversion-function-id: operator conversion-type-id Returns an IDENTIFIER_NODE representing the operator. */ static tree cp_parser_conversion_function_id (cp_parser* parser) { tree type; tree saved_scope; tree saved_qualifying_scope; tree saved_object_scope; tree pushed_scope = NULL_TREE; /* Look for the `operator' token. */ if (!cp_parser_require_keyword (parser, RID_OPERATOR, "`operator'")) return error_mark_node; /* When we parse the conversion-type-id, the current scope will be reset. However, we need that information in able to look up the conversion function later, so we save it here. */ saved_scope = parser->scope; saved_qualifying_scope = parser->qualifying_scope; saved_object_scope = parser->object_scope; /* We must enter the scope of the class so that the names of entities declared within the class are available in the conversion-type-id. For example, consider: struct S { typedef int I; operator I(); }; S::operator I() { ... } In order to see that `I' is a type-name in the definition, we must be in the scope of `S'. */ if (saved_scope) pushed_scope = push_scope (saved_scope); /* Parse the conversion-type-id. */ type = cp_parser_conversion_type_id (parser); /* Leave the scope of the class, if any. */ if (pushed_scope) pop_scope (pushed_scope); /* Restore the saved scope. */ parser->scope = saved_scope; parser->qualifying_scope = saved_qualifying_scope; parser->object_scope = saved_object_scope; /* If the TYPE is invalid, indicate failure. */ if (type == error_mark_node) return error_mark_node; return mangle_conv_op_name_for_type (type); } /* Parse a conversion-type-id: conversion-type-id: type-specifier-seq conversion-declarator [opt] Returns the TYPE specified. */ static tree cp_parser_conversion_type_id (cp_parser* parser) { tree attributes; cp_decl_specifier_seq type_specifiers; cp_declarator *declarator; tree type_specified; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); /* Parse the type-specifiers. */ cp_parser_type_specifier_seq (parser, /*is_condition=*/false, &type_specifiers); /* If that didn't work, stop. */ if (type_specifiers.type == error_mark_node) return error_mark_node; /* Parse the conversion-declarator. */ declarator = cp_parser_conversion_declarator_opt (parser); type_specified = grokdeclarator (declarator, &type_specifiers, TYPENAME, /*initialized=*/0, &attributes); if (attributes) cplus_decl_attributes (&type_specified, attributes, /*flags=*/0); return type_specified; } /* Parse an (optional) conversion-declarator. conversion-declarator: ptr-operator conversion-declarator [opt] */ static cp_declarator * cp_parser_conversion_declarator_opt (cp_parser* parser) { enum tree_code code; tree class_type; cp_cv_quals cv_quals; /* We don't know if there's a ptr-operator next, or not. */ cp_parser_parse_tentatively (parser); /* Try the ptr-operator. */ code = cp_parser_ptr_operator (parser, &class_type, &cv_quals); /* If it worked, look for more conversion-declarators. */ if (cp_parser_parse_definitely (parser)) { cp_declarator *declarator; /* Parse another optional declarator. */ declarator = cp_parser_conversion_declarator_opt (parser); return cp_parser_make_indirect_declarator (code, class_type, cv_quals, declarator); } return NULL; } /* Parse an (optional) ctor-initializer. ctor-initializer: : mem-initializer-list Returns TRUE iff the ctor-initializer was actually present. */ static bool cp_parser_ctor_initializer_opt (cp_parser* parser) { /* If the next token is not a `:', then there is no ctor-initializer. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COLON)) { /* Do default initialization of any bases and members. */ if (DECL_CONSTRUCTOR_P (current_function_decl)) finish_mem_initializers (NULL_TREE); return false; } /* Consume the `:' token. */ cp_lexer_consume_token (parser->lexer); /* And the mem-initializer-list. */ cp_parser_mem_initializer_list (parser); return true; } /* Parse a mem-initializer-list. mem-initializer-list: mem-initializer ... [opt] mem-initializer ... [opt] , mem-initializer-list */ static void cp_parser_mem_initializer_list (cp_parser* parser) { tree mem_initializer_list = NULL_TREE; /* Let the semantic analysis code know that we are starting the mem-initializer-list. */ if (!DECL_CONSTRUCTOR_P (current_function_decl)) error ("only constructors take base initializers"); /* Loop through the list. */ while (true) { tree mem_initializer; /* Parse the mem-initializer. */ mem_initializer = cp_parser_mem_initializer (parser); /* If the next token is a `...', we're expanding member initializers. */ if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...'. */ cp_lexer_consume_token (parser->lexer); /* The TREE_PURPOSE must be a _TYPE, because base-specifiers can be expanded but members cannot. */ if (mem_initializer != error_mark_node && !TYPE_P (TREE_PURPOSE (mem_initializer))) { error ("cannot expand initializer for member %<%D%>", TREE_PURPOSE (mem_initializer)); mem_initializer = error_mark_node; } /* Construct the pack expansion type. */ if (mem_initializer != error_mark_node) mem_initializer = make_pack_expansion (mem_initializer); } /* Add it to the list, unless it was erroneous. */ if (mem_initializer != error_mark_node) { TREE_CHAIN (mem_initializer) = mem_initializer_list; mem_initializer_list = mem_initializer; } /* If the next token is not a `,', we're done. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } /* Perform semantic analysis. */ if (DECL_CONSTRUCTOR_P (current_function_decl)) finish_mem_initializers (mem_initializer_list); } /* Parse a mem-initializer. mem-initializer: mem-initializer-id ( expression-list [opt] ) GNU extension: mem-initializer: ( expression-list [opt] ) Returns a TREE_LIST. The TREE_PURPOSE is the TYPE (for a base class) or FIELD_DECL (for a non-static data member) to initialize; the TREE_VALUE is the expression-list. An empty initialization list is represented by void_list_node. */ static tree cp_parser_mem_initializer (cp_parser* parser) { tree mem_initializer_id; tree expression_list; tree member; /* Find out what is being initialized. */ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN)) { pedwarn ("anachronistic old-style base class initializer"); mem_initializer_id = NULL_TREE; } else mem_initializer_id = cp_parser_mem_initializer_id (parser); member = expand_member_init (mem_initializer_id); if (member && !DECL_P (member)) in_base_initializer = 1; expression_list = cp_parser_parenthesized_expression_list (parser, false, /*cast_p=*/false, /*allow_expansion_p=*/true, /*non_constant_p=*/NULL); if (expression_list == error_mark_node) return error_mark_node; if (!expression_list) expression_list = void_type_node; in_base_initializer = 0; return member ? build_tree_list (member, expression_list) : error_mark_node; } /* Parse a mem-initializer-id. mem-initializer-id: :: [opt] nested-name-specifier [opt] class-name identifier Returns a TYPE indicating the class to be initializer for the first production. Returns an IDENTIFIER_NODE indicating the data member to be initialized for the second production. */ static tree cp_parser_mem_initializer_id (cp_parser* parser) { bool global_scope_p; bool nested_name_specifier_p; bool template_p = false; tree id; /* `typename' is not allowed in this context ([temp.res]). */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TYPENAME)) { error ("keyword % not allowed in this context (a qualified " "member initializer is implicitly a type)"); cp_lexer_consume_token (parser->lexer); } /* Look for the optional `::' operator. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the optional nested-name-specifier. The simplest way to implement: [temp.res] The keyword `typename' is not permitted in a base-specifier or mem-initializer; in these contexts a qualified name that depends on a template-parameter is implicitly assumed to be a type name. is to assume that we have seen the `typename' keyword at this point. */ nested_name_specifier_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, /*is_declaration=*/true) != NULL_TREE); if (nested_name_specifier_p) template_p = cp_parser_optional_template_keyword (parser); /* If there is a `::' operator or a nested-name-specifier, then we are definitely looking for a class-name. */ if (global_scope_p || nested_name_specifier_p) return cp_parser_class_name (parser, /*typename_keyword_p=*/true, /*template_keyword_p=*/template_p, none_type, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/true); /* Otherwise, we could also be looking for an ordinary identifier. */ cp_parser_parse_tentatively (parser); /* Try a class-name. */ id = cp_parser_class_name (parser, /*typename_keyword_p=*/true, /*template_keyword_p=*/false, none_type, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/true); /* If we found one, we're done. */ if (cp_parser_parse_definitely (parser)) return id; /* Otherwise, look for an ordinary identifier. */ return cp_parser_identifier (parser); } /* Overloading [gram.over] */ /* Parse an operator-function-id. operator-function-id: operator operator Returns an IDENTIFIER_NODE for the operator which is a human-readable spelling of the identifier, e.g., `operator +'. */ static tree cp_parser_operator_function_id (cp_parser* parser) { /* Look for the `operator' keyword. */ if (!cp_parser_require_keyword (parser, RID_OPERATOR, "`operator'")) return error_mark_node; /* And then the name of the operator itself. */ return cp_parser_operator (parser); } /* Parse an operator. operator: new delete new[] delete[] + - * / % ^ & | ~ ! = < > += -= *= /= %= ^= &= |= << >> >>= <<= == != <= >= && || ++ -- , ->* -> () [] GNU Extensions: operator: ? ?= Returns an IDENTIFIER_NODE for the operator which is a human-readable spelling of the identifier, e.g., `operator +'. */ static tree cp_parser_operator (cp_parser* parser) { tree id = NULL_TREE; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Figure out which operator we have. */ switch (token->type) { case CPP_KEYWORD: { enum tree_code op; /* The keyword should be either `new' or `delete'. */ if (token->keyword == RID_NEW) op = NEW_EXPR; else if (token->keyword == RID_DELETE) op = DELETE_EXPR; else break; /* Consume the `new' or `delete' token. */ cp_lexer_consume_token (parser->lexer); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `[' token then this is the array variant of the operator. */ if (token->type == CPP_OPEN_SQUARE) { /* Consume the `[' token. */ cp_lexer_consume_token (parser->lexer); /* Look for the `]' token. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); id = ansi_opname (op == NEW_EXPR ? VEC_NEW_EXPR : VEC_DELETE_EXPR); } /* Otherwise, we have the non-array variant. */ else id = ansi_opname (op); return id; } case CPP_PLUS: id = ansi_opname (PLUS_EXPR); break; case CPP_MINUS: id = ansi_opname (MINUS_EXPR); break; case CPP_MULT: id = ansi_opname (MULT_EXPR); break; case CPP_DIV: id = ansi_opname (TRUNC_DIV_EXPR); break; case CPP_MOD: id = ansi_opname (TRUNC_MOD_EXPR); break; case CPP_XOR: id = ansi_opname (BIT_XOR_EXPR); break; case CPP_AND: id = ansi_opname (BIT_AND_EXPR); break; case CPP_OR: id = ansi_opname (BIT_IOR_EXPR); break; case CPP_COMPL: id = ansi_opname (BIT_NOT_EXPR); break; case CPP_NOT: id = ansi_opname (TRUTH_NOT_EXPR); break; case CPP_EQ: id = ansi_assopname (NOP_EXPR); break; case CPP_LESS: id = ansi_opname (LT_EXPR); break; case CPP_GREATER: id = ansi_opname (GT_EXPR); break; case CPP_PLUS_EQ: id = ansi_assopname (PLUS_EXPR); break; case CPP_MINUS_EQ: id = ansi_assopname (MINUS_EXPR); break; case CPP_MULT_EQ: id = ansi_assopname (MULT_EXPR); break; case CPP_DIV_EQ: id = ansi_assopname (TRUNC_DIV_EXPR); break; case CPP_MOD_EQ: id = ansi_assopname (TRUNC_MOD_EXPR); break; case CPP_XOR_EQ: id = ansi_assopname (BIT_XOR_EXPR); break; case CPP_AND_EQ: id = ansi_assopname (BIT_AND_EXPR); break; case CPP_OR_EQ: id = ansi_assopname (BIT_IOR_EXPR); break; case CPP_LSHIFT: id = ansi_opname (LSHIFT_EXPR); break; case CPP_RSHIFT: id = ansi_opname (RSHIFT_EXPR); break; case CPP_LSHIFT_EQ: id = ansi_assopname (LSHIFT_EXPR); break; case CPP_RSHIFT_EQ: id = ansi_assopname (RSHIFT_EXPR); break; case CPP_EQ_EQ: id = ansi_opname (EQ_EXPR); break; case CPP_NOT_EQ: id = ansi_opname (NE_EXPR); break; case CPP_LESS_EQ: id = ansi_opname (LE_EXPR); break; case CPP_GREATER_EQ: id = ansi_opname (GE_EXPR); break; case CPP_AND_AND: id = ansi_opname (TRUTH_ANDIF_EXPR); break; case CPP_OR_OR: id = ansi_opname (TRUTH_ORIF_EXPR); break; case CPP_PLUS_PLUS: id = ansi_opname (POSTINCREMENT_EXPR); break; case CPP_MINUS_MINUS: id = ansi_opname (PREDECREMENT_EXPR); break; case CPP_COMMA: id = ansi_opname (COMPOUND_EXPR); break; case CPP_DEREF_STAR: id = ansi_opname (MEMBER_REF); break; case CPP_DEREF: id = ansi_opname (COMPONENT_REF); break; case CPP_OPEN_PAREN: /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Look for the matching `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); return ansi_opname (CALL_EXPR); case CPP_OPEN_SQUARE: /* Consume the `['. */ cp_lexer_consume_token (parser->lexer); /* Look for the matching `]'. */ cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'"); return ansi_opname (ARRAY_REF); default: /* Anything else is an error. */ break; } /* If we have selected an identifier, we need to consume the operator token. */ if (id) cp_lexer_consume_token (parser->lexer); /* Otherwise, no valid operator name was present. */ else { cp_parser_error (parser, "expected operator"); id = error_mark_node; } return id; } /* Parse a template-declaration. template-declaration: export [opt] template < template-parameter-list > declaration If MEMBER_P is TRUE, this template-declaration occurs within a class-specifier. The grammar rule given by the standard isn't correct. What is really meant is: template-declaration: export [opt] template-parameter-list-seq decl-specifier-seq [opt] init-declarator [opt] ; export [opt] template-parameter-list-seq function-definition template-parameter-list-seq: template-parameter-list-seq [opt] template < template-parameter-list > */ static void cp_parser_template_declaration (cp_parser* parser, bool member_p) { /* Check for `export'. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_EXPORT)) { /* Consume the `export' token. */ cp_lexer_consume_token (parser->lexer); /* Warn that we do not support `export'. */ warning (0, "keyword % not implemented, and will be ignored"); } cp_parser_template_declaration_after_export (parser, member_p); } /* Parse a template-parameter-list. template-parameter-list: template-parameter template-parameter-list , template-parameter Returns a TREE_LIST. Each node represents a template parameter. The nodes are connected via their TREE_CHAINs. */ static tree cp_parser_template_parameter_list (cp_parser* parser) { tree parameter_list = NULL_TREE; begin_template_parm_list (); while (true) { tree parameter; cp_token *token; bool is_non_type; bool is_parameter_pack; /* Parse the template-parameter. */ parameter = cp_parser_template_parameter (parser, &is_non_type, &is_parameter_pack); /* Add it to the list. */ if (parameter != error_mark_node) parameter_list = process_template_parm (parameter_list, parameter, is_non_type, is_parameter_pack); else { tree err_parm = build_tree_list (parameter, parameter); TREE_VALUE (err_parm) = error_mark_node; parameter_list = chainon (parameter_list, err_parm); } /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's not a `,', we're done. */ if (token->type != CPP_COMMA) break; /* Otherwise, consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } return end_template_parm_list (parameter_list); } /* Parse a template-parameter. template-parameter: type-parameter parameter-declaration If all goes well, returns a TREE_LIST. The TREE_VALUE represents the parameter. The TREE_PURPOSE is the default value, if any. Returns ERROR_MARK_NODE on failure. *IS_NON_TYPE is set to true iff this parameter is a non-type parameter. *IS_PARAMETER_PACK is set to true iff this parameter is a parameter pack. */ static tree cp_parser_template_parameter (cp_parser* parser, bool *is_non_type, bool *is_parameter_pack) { cp_token *token; cp_parameter_declarator *parameter_declarator; cp_declarator *id_declarator; tree parm; /* Assume it is a type parameter or a template parameter. */ *is_non_type = false; /* Assume it not a parameter pack. */ *is_parameter_pack = false; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it is `class' or `template', we have a type-parameter. */ if (token->keyword == RID_TEMPLATE) return cp_parser_type_parameter (parser, is_parameter_pack); /* If it is `class' or `typename' we do not know yet whether it is a type parameter or a non-type parameter. Consider: template ... or: template ... Here, the first parameter is a type parameter, and the second is a non-type parameter. We can tell by looking at the token after the identifier -- if it is a `,', `=', or `>' then we have a type parameter. */ if (token->keyword == RID_TYPENAME || token->keyword == RID_CLASS) { /* Peek at the token after `class' or `typename'. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); /* If it's an ellipsis, we have a template type parameter pack. */ if (token->type == CPP_ELLIPSIS) return cp_parser_type_parameter (parser, is_parameter_pack); /* If it's an identifier, skip it. */ if (token->type == CPP_NAME) token = cp_lexer_peek_nth_token (parser->lexer, 3); /* Now, see if the token looks like the end of a template parameter. */ if (token->type == CPP_COMMA || token->type == CPP_EQ || token->type == CPP_GREATER) return cp_parser_type_parameter (parser, is_parameter_pack); } /* Otherwise, it is a non-type parameter. [temp.param] When parsing a default template-argument for a non-type template-parameter, the first non-nested `>' is taken as the end of the template parameter-list rather than a greater-than operator. */ *is_non_type = true; parameter_declarator = cp_parser_parameter_declaration (parser, /*template_parm_p=*/true, /*parenthesized_p=*/NULL); /* If the parameter declaration is marked as a parameter pack, set *IS_PARAMETER_PACK to notify the caller. Also, unmark the declarator's PACK_EXPANSION_P, otherwise we'll get errors from grokdeclarator. */ if (parameter_declarator && parameter_declarator->declarator && parameter_declarator->declarator->parameter_pack_p) { *is_parameter_pack = true; parameter_declarator->declarator->parameter_pack_p = false; } /* If the next token is an ellipsis, and we don't already have it marked as a parameter pack, then we have a parameter pack (that has no declarator). */ if (!*is_parameter_pack && cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS) && declarator_can_be_parameter_pack (parameter_declarator->declarator)) { /* Consume the `...'. */ cp_lexer_consume_token (parser->lexer); maybe_warn_variadic_templates (); *is_parameter_pack = true; } /* We might end up with a pack expansion as the type of the non-type template parameter, in which case this is a non-type template parameter pack. */ else if (parameter_declarator && parameter_declarator->decl_specifiers.type && PACK_EXPANSION_P (parameter_declarator->decl_specifiers.type)) { *is_parameter_pack = true; parameter_declarator->decl_specifiers.type = PACK_EXPANSION_PATTERN (parameter_declarator->decl_specifiers.type); } if (*is_parameter_pack && cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { /* Parameter packs cannot have default arguments. However, a user may try to do so, so we'll parse them and give an appropriate diagnostic here. */ /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* Find the name of the parameter pack. */ id_declarator = parameter_declarator->declarator; while (id_declarator && id_declarator->kind != cdk_id) id_declarator = id_declarator->declarator; if (id_declarator && id_declarator->kind == cdk_id) error ("template parameter pack %qD cannot have a default argument", id_declarator->u.id.unqualified_name); else error ("template parameter pack cannot have a default argument"); /* Parse the default argument, but throw away the result. */ cp_parser_default_argument (parser, /*template_parm_p=*/true); } parm = grokdeclarator (parameter_declarator->declarator, ¶meter_declarator->decl_specifiers, PARM, /*initialized=*/0, /*attrlist=*/NULL); if (parm == error_mark_node) return error_mark_node; return build_tree_list (parameter_declarator->default_argument, parm); } /* Parse a type-parameter. type-parameter: class identifier [opt] class identifier [opt] = type-id typename identifier [opt] typename identifier [opt] = type-id template < template-parameter-list > class identifier [opt] template < template-parameter-list > class identifier [opt] = id-expression GNU Extension (variadic templates): type-parameter: class ... identifier [opt] typename ... identifier [opt] Returns a TREE_LIST. The TREE_VALUE is itself a TREE_LIST. The TREE_PURPOSE is the default-argument, if any. The TREE_VALUE is the declaration of the parameter. Sets *IS_PARAMETER_PACK if this is a template parameter pack. */ static tree cp_parser_type_parameter (cp_parser* parser, bool *is_parameter_pack) { cp_token *token; tree parameter; /* Look for a keyword to tell us what kind of parameter this is. */ token = cp_parser_require (parser, CPP_KEYWORD, "`class', `typename', or `template'"); if (!token) return error_mark_node; switch (token->keyword) { case RID_CLASS: case RID_TYPENAME: { tree identifier; tree default_argument; /* If the next token is an ellipsis, we have a template argument pack. */ if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); maybe_warn_variadic_templates (); *is_parameter_pack = true; } /* If the next token is an identifier, then it names the parameter. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) identifier = cp_parser_identifier (parser); else identifier = NULL_TREE; /* Create the parameter. */ parameter = finish_template_type_parm (class_type_node, identifier); /* If the next token is an `=', we have a default argument. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { /* Consume the `=' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the default-argument. */ push_deferring_access_checks (dk_no_deferred); default_argument = cp_parser_type_id (parser); /* Template parameter packs cannot have default arguments. */ if (*is_parameter_pack) { if (identifier) error ("template parameter pack %qD cannot have a default argument", identifier); else error ("template parameter packs cannot have default arguments"); default_argument = NULL_TREE; } pop_deferring_access_checks (); } else default_argument = NULL_TREE; /* Create the combined representation of the parameter and the default argument. */ parameter = build_tree_list (default_argument, parameter); } break; case RID_TEMPLATE: { tree parameter_list; tree identifier; tree default_argument; /* Look for the `<'. */ cp_parser_require (parser, CPP_LESS, "`<'"); /* Parse the template-parameter-list. */ parameter_list = cp_parser_template_parameter_list (parser); /* Look for the `>'. */ cp_parser_require (parser, CPP_GREATER, "`>'"); /* Look for the `class' keyword. */ cp_parser_require_keyword (parser, RID_CLASS, "`class'"); /* If the next token is an ellipsis, we have a template argument pack. */ if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); maybe_warn_variadic_templates (); *is_parameter_pack = true; } /* If the next token is an `=', then there is a default-argument. If the next token is a `>', we are at the end of the parameter-list. If the next token is a `,', then we are at the end of this parameter. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_EQ) && cp_lexer_next_token_is_not (parser->lexer, CPP_GREATER) && cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) { identifier = cp_parser_identifier (parser); /* Treat invalid names as if the parameter were nameless. */ if (identifier == error_mark_node) identifier = NULL_TREE; } else identifier = NULL_TREE; /* Create the template parameter. */ parameter = finish_template_template_parm (class_type_node, identifier); /* If the next token is an `=', then there is a default-argument. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { bool is_template; /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* Parse the id-expression. */ push_deferring_access_checks (dk_no_deferred); default_argument = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*template_p=*/&is_template, /*declarator_p=*/false, /*optional_p=*/false); if (TREE_CODE (default_argument) == TYPE_DECL) /* If the id-expression was a template-id that refers to a template-class, we already have the declaration here, so no further lookup is needed. */ ; else /* Look up the name. */ default_argument = cp_parser_lookup_name (parser, default_argument, none_type, /*is_template=*/is_template, /*is_namespace=*/false, /*check_dependency=*/true, /*ambiguous_decls=*/NULL); /* See if the default argument is valid. */ default_argument = check_template_template_default_arg (default_argument); /* Template parameter packs cannot have default arguments. */ if (*is_parameter_pack) { if (identifier) error ("template parameter pack %qD cannot have a default argument", identifier); else error ("template parameter packs cannot have default arguments"); default_argument = NULL_TREE; } pop_deferring_access_checks (); } else default_argument = NULL_TREE; /* Create the combined representation of the parameter and the default argument. */ parameter = build_tree_list (default_argument, parameter); } break; default: gcc_unreachable (); break; } return parameter; } /* Parse a template-id. template-id: template-name < template-argument-list [opt] > If TEMPLATE_KEYWORD_P is TRUE, then we have just seen the `template' keyword. In this case, a TEMPLATE_ID_EXPR will be returned. Otherwise, if the template-name names a function, or set of functions, returns a TEMPLATE_ID_EXPR. If the template-name names a class, returns a TYPE_DECL for the specialization. If CHECK_DEPENDENCY_P is FALSE, names are looked up in uninstantiated templates. */ static tree cp_parser_template_id (cp_parser *parser, bool template_keyword_p, bool check_dependency_p, bool is_declaration) { int i; tree template; tree arguments; tree template_id; cp_token_position start_of_id = 0; deferred_access_check *chk; VEC (deferred_access_check,gc) *access_check; cp_token *next_token, *next_token_2; bool is_identifier; /* If the next token corresponds to a template-id, there is no need to reparse it. */ next_token = cp_lexer_peek_token (parser->lexer); if (next_token->type == CPP_TEMPLATE_ID) { struct tree_check *check_value; /* Get the stored value. */ check_value = cp_lexer_consume_token (parser->lexer)->u.tree_check_value; /* Perform any access checks that were deferred. */ access_check = check_value->checks; if (access_check) { for (i = 0 ; VEC_iterate (deferred_access_check, access_check, i, chk) ; ++i) { perform_or_defer_access_check (chk->binfo, chk->decl, chk->diag_decl); } } /* Return the stored value. */ return check_value->value; } /* Avoid performing name lookup if there is no possibility of finding a template-id. */ if ((next_token->type != CPP_NAME && next_token->keyword != RID_OPERATOR) || (next_token->type == CPP_NAME && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2))) { cp_parser_error (parser, "expected template-id"); return error_mark_node; } /* Remember where the template-id starts. */ if (cp_parser_uncommitted_to_tentative_parse_p (parser)) start_of_id = cp_lexer_token_position (parser->lexer, false); push_deferring_access_checks (dk_deferred); /* Parse the template-name. */ is_identifier = false; template = cp_parser_template_name (parser, template_keyword_p, check_dependency_p, is_declaration, &is_identifier); if (template == error_mark_node || is_identifier) { pop_deferring_access_checks (); return template; } /* If we find the sequence `[:' after a template-name, it's probably a digraph-typo for `< ::'. Substitute the tokens and check if we can parse correctly the argument list. */ next_token = cp_lexer_peek_token (parser->lexer); next_token_2 = cp_lexer_peek_nth_token (parser->lexer, 2); if (next_token->type == CPP_OPEN_SQUARE && next_token->flags & DIGRAPH && next_token_2->type == CPP_COLON && !(next_token_2->flags & PREV_WHITE)) { cp_parser_parse_tentatively (parser); /* Change `:' into `::'. */ next_token_2->type = CPP_SCOPE; /* Consume the first token (CPP_OPEN_SQUARE - which we pretend it is CPP_LESS. */ cp_lexer_consume_token (parser->lexer); /* Parse the arguments. */ arguments = cp_parser_enclosed_template_argument_list (parser); if (!cp_parser_parse_definitely (parser)) { /* If we couldn't parse an argument list, then we revert our changes and return simply an error. Maybe this is not a template-id after all. */ next_token_2->type = CPP_COLON; cp_parser_error (parser, "expected %<<%>"); pop_deferring_access_checks (); return error_mark_node; } /* Otherwise, emit an error about the invalid digraph, but continue parsing because we got our argument list. */ permerror ("%<<::%> cannot begin a template-argument list"); inform ("%<<:%> is an alternate spelling for %<[%>. Insert whitespace " "between %<<%> and %<::%>"); if (!flag_permissive) { static bool hint; if (!hint) { inform ("(if you use -fpermissive G++ will accept your code)"); hint = true; } } } else { /* Look for the `<' that starts the template-argument-list. */ if (!cp_parser_require (parser, CPP_LESS, "`<'")) { pop_deferring_access_checks (); return error_mark_node; } /* Parse the arguments. */ arguments = cp_parser_enclosed_template_argument_list (parser); } /* Build a representation of the specialization. */ if (TREE_CODE (template) == IDENTIFIER_NODE) template_id = build_min_nt (TEMPLATE_ID_EXPR, template, arguments); else if (DECL_CLASS_TEMPLATE_P (template) || DECL_TEMPLATE_TEMPLATE_PARM_P (template)) { bool entering_scope; /* In "template ... A::", A is the abstract A template (rather than some instantiation thereof) only if is not nested within some other construct. For example, in "template void f(T) { A::", A is just an instantiation of A. */ entering_scope = (template_parm_scope_p () && cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)); template_id = finish_template_type (template, arguments, entering_scope); } else { /* If it's not a class-template or a template-template, it should be a function-template. */ gcc_assert ((DECL_FUNCTION_TEMPLATE_P (template) || TREE_CODE (template) == OVERLOAD || BASELINK_P (template))); template_id = lookup_template_function (template, arguments); } /* If parsing tentatively, replace the sequence of tokens that makes up the template-id with a CPP_TEMPLATE_ID token. That way, should we re-parse the token stream, we will not have to repeat the effort required to do the parse, nor will we issue duplicate error messages about problems during instantiation of the template. */ if (start_of_id) { cp_token *token = cp_lexer_token_at (parser->lexer, start_of_id); /* Reset the contents of the START_OF_ID token. */ token->type = CPP_TEMPLATE_ID; /* Retrieve any deferred checks. Do not pop this access checks yet so the memory will not be reclaimed during token replacing below. */ token->u.tree_check_value = GGC_CNEW (struct tree_check); token->u.tree_check_value->value = template_id; token->u.tree_check_value->checks = get_deferred_access_checks (); token->keyword = RID_MAX; /* Purge all subsequent tokens. */ cp_lexer_purge_tokens_after (parser->lexer, start_of_id); /* ??? Can we actually assume that, if template_id == error_mark_node, we will have issued a diagnostic to the user, as opposed to simply marking the tentative parse as failed? */ if (cp_parser_error_occurred (parser) && template_id != error_mark_node) error ("parse error in template argument list"); } pop_deferring_access_checks (); return template_id; } /* Parse a template-name. template-name: identifier The standard should actually say: template-name: identifier operator-function-id A defect report has been filed about this issue. A conversion-function-id cannot be a template name because they cannot be part of a template-id. In fact, looking at this code: a.operator K() the conversion-function-id is "operator K", and K is a type-id. It is impossible to call a templated conversion-function-id with an explicit argument list, since the only allowed template parameter is the type to which it is converting. If TEMPLATE_KEYWORD_P is true, then we have just seen the `template' keyword, in a construction like: T::template f<3>() In that case `f' is taken to be a template-name, even though there is no way of knowing for sure. Returns the TEMPLATE_DECL for the template, or an OVERLOAD if the name refers to a set of overloaded functions, at least one of which is a template, or an IDENTIFIER_NODE with the name of the template, if TEMPLATE_KEYWORD_P is true. If CHECK_DEPENDENCY_P is FALSE, names are looked up inside uninstantiated templates. */ static tree cp_parser_template_name (cp_parser* parser, bool template_keyword_p, bool check_dependency_p, bool is_declaration, bool *is_identifier) { tree identifier; tree decl; tree fns; /* If the next token is `operator', then we have either an operator-function-id or a conversion-function-id. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_OPERATOR)) { /* We don't know whether we're looking at an operator-function-id or a conversion-function-id. */ cp_parser_parse_tentatively (parser); /* Try an operator-function-id. */ identifier = cp_parser_operator_function_id (parser); /* If that didn't work, try a conversion-function-id. */ if (!cp_parser_parse_definitely (parser)) { cp_parser_error (parser, "expected template-name"); return error_mark_node; } } /* Look for the identifier. */ else identifier = cp_parser_identifier (parser); /* If we didn't find an identifier, we don't have a template-id. */ if (identifier == error_mark_node) return error_mark_node; /* If the name immediately followed the `template' keyword, then it is a template-name. However, if the next token is not `<', then we do not treat it as a template-name, since it is not being used as part of a template-id. This enables us to handle constructs like: template struct S { S(); }; template S::S(); correctly. We would treat `S' as a template -- if it were `S' -- but we do not if there is no `<'. */ if (processing_template_decl && cp_parser_nth_token_starts_template_argument_list_p (parser, 1)) { /* In a declaration, in a dependent context, we pretend that the "template" keyword was present in order to improve error recovery. For example, given: template void f(T::X); we want to treat "X" as a template-id. */ if (is_declaration && !template_keyword_p && parser->scope && TYPE_P (parser->scope) && check_dependency_p && dependent_type_p (parser->scope) /* Do not do this for dtors (or ctors), since they never need the template keyword before their name. */ && !constructor_name_p (identifier, parser->scope)) { cp_token_position start = 0; /* Explain what went wrong. */ error ("non-template %qD used as template", identifier); inform ("use %<%T::template %D%> to indicate that it is a template", parser->scope, identifier); /* If parsing tentatively, find the location of the "<" token. */ if (cp_parser_simulate_error (parser)) start = cp_lexer_token_position (parser->lexer, true); /* Parse the template arguments so that we can issue error messages about them. */ cp_lexer_consume_token (parser->lexer); cp_parser_enclosed_template_argument_list (parser); /* Skip tokens until we find a good place from which to continue parsing. */ cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/true, /*consume_paren=*/false); /* If parsing tentatively, permanently remove the template argument list. That will prevent duplicate error messages from being issued about the missing "template" keyword. */ if (start) cp_lexer_purge_tokens_after (parser->lexer, start); if (is_identifier) *is_identifier = true; return identifier; } /* If the "template" keyword is present, then there is generally no point in doing name-lookup, so we just return IDENTIFIER. But, if the qualifying scope is non-dependent then we can (and must) do name-lookup normally. */ if (template_keyword_p && (!parser->scope || (TYPE_P (parser->scope) && dependent_type_p (parser->scope)))) return identifier; } /* Look up the name. */ decl = cp_parser_lookup_name (parser, identifier, none_type, /*is_template=*/false, /*is_namespace=*/false, check_dependency_p, /*ambiguous_decls=*/NULL); decl = maybe_get_template_decl_from_type_decl (decl); /* If DECL is a template, then the name was a template-name. */ if (TREE_CODE (decl) == TEMPLATE_DECL) ; else { tree fn = NULL_TREE; /* The standard does not explicitly indicate whether a name that names a set of overloaded declarations, some of which are templates, is a template-name. However, such a name should be a template-name; otherwise, there is no way to form a template-id for the overloaded templates. */ fns = BASELINK_P (decl) ? BASELINK_FUNCTIONS (decl) : decl; if (TREE_CODE (fns) == OVERLOAD) for (fn = fns; fn; fn = OVL_NEXT (fn)) if (TREE_CODE (OVL_CURRENT (fn)) == TEMPLATE_DECL) break; if (!fn) { /* The name does not name a template. */ cp_parser_error (parser, "expected template-name"); return error_mark_node; } } /* If DECL is dependent, and refers to a function, then just return its name; we will look it up again during template instantiation. */ if (DECL_FUNCTION_TEMPLATE_P (decl) || !DECL_P (decl)) { tree scope = CP_DECL_CONTEXT (get_first_fn (decl)); if (TYPE_P (scope) && dependent_type_p (scope)) return identifier; } return decl; } /* Parse a template-argument-list. template-argument-list: template-argument ... [opt] template-argument-list , template-argument ... [opt] Returns a TREE_VEC containing the arguments. */ static tree cp_parser_template_argument_list (cp_parser* parser) { tree fixed_args[10]; unsigned n_args = 0; unsigned alloced = 10; tree *arg_ary = fixed_args; tree vec; bool saved_in_template_argument_list_p; bool saved_ice_p; bool saved_non_ice_p; saved_in_template_argument_list_p = parser->in_template_argument_list_p; parser->in_template_argument_list_p = true; /* Even if the template-id appears in an integral constant-expression, the contents of the argument list do not. */ saved_ice_p = parser->integral_constant_expression_p; parser->integral_constant_expression_p = false; saved_non_ice_p = parser->non_integral_constant_expression_p; parser->non_integral_constant_expression_p = false; /* Parse the arguments. */ do { tree argument; if (n_args) /* Consume the comma. */ cp_lexer_consume_token (parser->lexer); /* Parse the template-argument. */ argument = cp_parser_template_argument (parser); /* If the next token is an ellipsis, we're expanding a template argument pack. */ if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); /* Make the argument into a TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION. */ argument = make_pack_expansion (argument); } if (n_args == alloced) { alloced *= 2; if (arg_ary == fixed_args) { arg_ary = XNEWVEC (tree, alloced); memcpy (arg_ary, fixed_args, sizeof (tree) * n_args); } else arg_ary = XRESIZEVEC (tree, arg_ary, alloced); } arg_ary[n_args++] = argument; } while (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)); vec = make_tree_vec (n_args); while (n_args--) TREE_VEC_ELT (vec, n_args) = arg_ary[n_args]; if (arg_ary != fixed_args) free (arg_ary); parser->non_integral_constant_expression_p = saved_non_ice_p; parser->integral_constant_expression_p = saved_ice_p; parser->in_template_argument_list_p = saved_in_template_argument_list_p; return vec; } /* Parse a template-argument. template-argument: assignment-expression type-id id-expression The representation is that of an assignment-expression, type-id, or id-expression -- except that the qualified id-expression is evaluated, so that the value returned is either a DECL or an OVERLOAD. Although the standard says "assignment-expression", it forbids throw-expressions or assignments in the template argument. Therefore, we use "conditional-expression" instead. */ static tree cp_parser_template_argument (cp_parser* parser) { tree argument; bool template_p; bool address_p; bool maybe_type_id = false; cp_token *token; cp_id_kind idk; /* There's really no way to know what we're looking at, so we just try each alternative in order. [temp.arg] In a template-argument, an ambiguity between a type-id and an expression is resolved to a type-id, regardless of the form of the corresponding template-parameter. Therefore, we try a type-id first. */ cp_parser_parse_tentatively (parser); argument = cp_parser_type_id (parser); /* If there was no error parsing the type-id but the next token is a '>>', we probably found a typo for '> >'. But there are type-id which are also valid expressions. For instance: struct X { int operator >> (int); }; template struct Foo {}; Foo> 5> r; Here 'X()' is a valid type-id of a function type, but the user just wanted to write the expression "X() >> 5". Thus, we remember that we found a valid type-id, but we still try to parse the argument as an expression to see what happens. */ if (!cp_parser_error_occurred (parser) && cp_lexer_next_token_is (parser->lexer, CPP_RSHIFT)) { maybe_type_id = true; cp_parser_abort_tentative_parse (parser); } else { /* If the next token isn't a `,' or a `>', then this argument wasn't really finished. This means that the argument is not a valid type-id. */ if (!cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_error (parser, "expected template-argument"); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) return argument; } /* We're still not sure what the argument will be. */ cp_parser_parse_tentatively (parser); /* Try a template. */ argument = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, &template_p, /*declarator_p=*/false, /*optional_p=*/false); /* If the next token isn't a `,' or a `>', then this argument wasn't really finished. */ if (!cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_error (parser, "expected template-argument"); if (!cp_parser_error_occurred (parser)) { /* Figure out what is being referred to. If the id-expression was for a class template specialization, then we will have a TYPE_DECL at this point. There is no need to do name lookup at this point in that case. */ if (TREE_CODE (argument) != TYPE_DECL) argument = cp_parser_lookup_name (parser, argument, none_type, /*is_template=*/template_p, /*is_namespace=*/false, /*check_dependency=*/true, /*ambiguous_decls=*/NULL); if (TREE_CODE (argument) != TEMPLATE_DECL && TREE_CODE (argument) != UNBOUND_CLASS_TEMPLATE) cp_parser_error (parser, "expected template-name"); } if (cp_parser_parse_definitely (parser)) return argument; /* It must be a non-type argument. There permitted cases are given in [temp.arg.nontype]: -- an integral constant-expression of integral or enumeration type; or -- the name of a non-type template-parameter; or -- the name of an object or function with external linkage... -- the address of an object or function with external linkage... -- a pointer to member... */ /* Look for a non-type template parameter. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) { cp_parser_parse_tentatively (parser); argument = cp_parser_primary_expression (parser, /*adress_p=*/false, /*cast_p=*/false, /*template_arg_p=*/true, &idk); if (TREE_CODE (argument) != TEMPLATE_PARM_INDEX || !cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_simulate_error (parser); if (cp_parser_parse_definitely (parser)) return argument; } /* If the next token is "&", the argument must be the address of an object or function with external linkage. */ address_p = cp_lexer_next_token_is (parser->lexer, CPP_AND); if (address_p) cp_lexer_consume_token (parser->lexer); /* See if we might have an id-expression. */ token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_NAME || token->keyword == RID_OPERATOR || token->type == CPP_SCOPE || token->type == CPP_TEMPLATE_ID || token->type == CPP_NESTED_NAME_SPECIFIER) { cp_parser_parse_tentatively (parser); argument = cp_parser_primary_expression (parser, address_p, /*cast_p=*/false, /*template_arg_p=*/true, &idk); if (cp_parser_error_occurred (parser) || !cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_abort_tentative_parse (parser); else { if (TREE_CODE (argument) == INDIRECT_REF) { gcc_assert (REFERENCE_REF_P (argument)); argument = TREE_OPERAND (argument, 0); } if (TREE_CODE (argument) == VAR_DECL) { /* A variable without external linkage might still be a valid constant-expression, so no error is issued here if the external-linkage check fails. */ if (!address_p && !DECL_EXTERNAL_LINKAGE_P (argument)) cp_parser_simulate_error (parser); } else if (is_overloaded_fn (argument)) /* All overloaded functions are allowed; if the external linkage test does not pass, an error will be issued later. */ ; else if (address_p && (TREE_CODE (argument) == OFFSET_REF || TREE_CODE (argument) == SCOPE_REF)) /* A pointer-to-member. */ ; else if (TREE_CODE (argument) == TEMPLATE_PARM_INDEX) ; else cp_parser_simulate_error (parser); if (cp_parser_parse_definitely (parser)) { if (address_p) argument = build_x_unary_op (ADDR_EXPR, argument, tf_warning_or_error); return argument; } } } /* If the argument started with "&", there are no other valid alternatives at this point. */ if (address_p) { cp_parser_error (parser, "invalid non-type template argument"); return error_mark_node; } /* If the argument wasn't successfully parsed as a type-id followed by '>>', the argument can only be a constant expression now. Otherwise, we try parsing the constant-expression tentatively, because the argument could really be a type-id. */ if (maybe_type_id) cp_parser_parse_tentatively (parser); argument = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, /*non_constant_p=*/NULL); argument = fold_non_dependent_expr (argument); if (!maybe_type_id) return argument; if (!cp_parser_next_token_ends_template_argument_p (parser)) cp_parser_error (parser, "expected template-argument"); if (cp_parser_parse_definitely (parser)) return argument; /* We did our best to parse the argument as a non type-id, but that was the only alternative that matched (albeit with a '>' after it). We can assume it's just a typo from the user, and a diagnostic will then be issued. */ return cp_parser_type_id (parser); } /* Parse an explicit-instantiation. explicit-instantiation: template declaration Although the standard says `declaration', what it really means is: explicit-instantiation: template decl-specifier-seq [opt] declarator [opt] ; Things like `template int S::i = 5, int S::j;' are not supposed to be allowed. A defect report has been filed about this issue. GNU Extension: explicit-instantiation: storage-class-specifier template decl-specifier-seq [opt] declarator [opt] ; function-specifier template decl-specifier-seq [opt] declarator [opt] ; */ static void cp_parser_explicit_instantiation (cp_parser* parser) { int declares_class_or_enum; cp_decl_specifier_seq decl_specifiers; tree extension_specifier = NULL_TREE; /* Look for an (optional) storage-class-specifier or function-specifier. */ if (cp_parser_allow_gnu_extensions_p (parser)) { extension_specifier = cp_parser_storage_class_specifier_opt (parser); if (!extension_specifier) extension_specifier = cp_parser_function_specifier_opt (parser, /*decl_specs=*/NULL); } /* Look for the `template' keyword. */ cp_parser_require_keyword (parser, RID_TEMPLATE, "`template'"); /* Let the front end know that we are processing an explicit instantiation. */ begin_explicit_instantiation (); /* [temp.explicit] says that we are supposed to ignore access control while processing explicit instantiation directives. */ push_deferring_access_checks (dk_no_check); /* Parse a decl-specifier-seq. */ cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_OPTIONAL, &decl_specifiers, &declares_class_or_enum); /* If there was exactly one decl-specifier, and it declared a class, and there's no declarator, then we have an explicit type instantiation. */ if (declares_class_or_enum && cp_parser_declares_only_class_p (parser)) { tree type; type = check_tag_decl (&decl_specifiers); /* Turn access control back on for names used during template instantiation. */ pop_deferring_access_checks (); if (type) do_type_instantiation (type, extension_specifier, /*complain=*/tf_error); } else { cp_declarator *declarator; tree decl; /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL, /*member_p=*/false); if (declares_class_or_enum & 2) cp_parser_check_for_definition_in_return_type (declarator, decl_specifiers.type); if (declarator != cp_error_declarator) { decl = grokdeclarator (declarator, &decl_specifiers, NORMAL, 0, &decl_specifiers.attributes); /* Turn access control back on for names used during template instantiation. */ pop_deferring_access_checks (); /* Do the explicit instantiation. */ do_decl_instantiation (decl, extension_specifier); } else { pop_deferring_access_checks (); /* Skip the body of the explicit instantiation. */ cp_parser_skip_to_end_of_statement (parser); } } /* We're done with the instantiation. */ end_explicit_instantiation (); cp_parser_consume_semicolon_at_end_of_statement (parser); } /* Parse an explicit-specialization. explicit-specialization: template < > declaration Although the standard says `declaration', what it really means is: explicit-specialization: template <> decl-specifier [opt] init-declarator [opt] ; template <> function-definition template <> explicit-specialization template <> template-declaration */ static void cp_parser_explicit_specialization (cp_parser* parser) { bool need_lang_pop; /* Look for the `template' keyword. */ cp_parser_require_keyword (parser, RID_TEMPLATE, "`template'"); /* Look for the `<'. */ cp_parser_require (parser, CPP_LESS, "`<'"); /* Look for the `>'. */ cp_parser_require (parser, CPP_GREATER, "`>'"); /* We have processed another parameter list. */ ++parser->num_template_parameter_lists; /* [temp] A template ... explicit specialization ... shall not have C linkage. */ if (current_lang_name == lang_name_c) { error ("template specialization with C linkage"); /* Give it C++ linkage to avoid confusing other parts of the front end. */ push_lang_context (lang_name_cplusplus); need_lang_pop = true; } else need_lang_pop = false; /* Let the front end know that we are beginning a specialization. */ if (!begin_specialization ()) { end_specialization (); cp_parser_skip_to_end_of_block_or_statement (parser); return; } /* If the next keyword is `template', we need to figure out whether or not we're looking a template-declaration. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TEMPLATE)) { if (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_LESS && cp_lexer_peek_nth_token (parser->lexer, 3)->type != CPP_GREATER) cp_parser_template_declaration_after_export (parser, /*member_p=*/false); else cp_parser_explicit_specialization (parser); } else /* Parse the dependent declaration. */ cp_parser_single_declaration (parser, /*checks=*/NULL, /*member_p=*/false, /*explicit_specialization_p=*/true, /*friend_p=*/NULL); /* We're done with the specialization. */ end_specialization (); /* For the erroneous case of a template with C linkage, we pushed an implicit C++ linkage scope; exit that scope now. */ if (need_lang_pop) pop_lang_context (); /* We're done with this parameter list. */ --parser->num_template_parameter_lists; } /* Parse a type-specifier. type-specifier: simple-type-specifier class-specifier enum-specifier elaborated-type-specifier cv-qualifier GNU Extension: type-specifier: __complex__ Returns a representation of the type-specifier. For a class-specifier, enum-specifier, or elaborated-type-specifier, a TREE_TYPE is returned; otherwise, a TYPE_DECL is returned. The parser flags FLAGS is used to control type-specifier parsing. If IS_DECLARATION is TRUE, then this type-specifier is appearing in a decl-specifier-seq. If DECLARES_CLASS_OR_ENUM is non-NULL, and the type-specifier is a class-specifier, enum-specifier, or elaborated-type-specifier, then *DECLARES_CLASS_OR_ENUM is set to a nonzero value. The value is 1 if a type is declared; 2 if it is defined. Otherwise, it is set to zero. If IS_CV_QUALIFIER is non-NULL, and the type-specifier is a cv-qualifier, then IS_CV_QUALIFIER is set to TRUE. Otherwise, it is set to FALSE. */ static tree cp_parser_type_specifier (cp_parser* parser, cp_parser_flags flags, cp_decl_specifier_seq *decl_specs, bool is_declaration, int* declares_class_or_enum, bool* is_cv_qualifier) { tree type_spec = NULL_TREE; cp_token *token; enum rid keyword; cp_decl_spec ds = ds_last; /* Assume this type-specifier does not declare a new type. */ if (declares_class_or_enum) *declares_class_or_enum = 0; /* And that it does not specify a cv-qualifier. */ if (is_cv_qualifier) *is_cv_qualifier = false; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we're looking at a keyword, we can use that to guide the production we choose. */ keyword = token->keyword; switch (keyword) { case RID_ENUM: /* Look for the enum-specifier. */ type_spec = cp_parser_enum_specifier (parser); /* If that worked, we're done. */ if (type_spec) { if (declares_class_or_enum) *declares_class_or_enum = 2; if (decl_specs) cp_parser_set_decl_spec_type (decl_specs, type_spec, /*user_defined_p=*/true); return type_spec; } else goto elaborated_type_specifier; /* Any of these indicate either a class-specifier, or an elaborated-type-specifier. */ case RID_CLASS: case RID_STRUCT: case RID_UNION: /* Parse tentatively so that we can back up if we don't find a class-specifier. */ cp_parser_parse_tentatively (parser); /* Look for the class-specifier. */ type_spec = cp_parser_class_specifier (parser); /* If that worked, we're done. */ if (cp_parser_parse_definitely (parser)) { if (declares_class_or_enum) *declares_class_or_enum = 2; if (decl_specs) cp_parser_set_decl_spec_type (decl_specs, type_spec, /*user_defined_p=*/true); return type_spec; } /* Fall through. */ elaborated_type_specifier: /* We're declaring (not defining) a class or enum. */ if (declares_class_or_enum) *declares_class_or_enum = 1; /* Fall through. */ case RID_TYPENAME: /* Look for an elaborated-type-specifier. */ type_spec = (cp_parser_elaborated_type_specifier (parser, decl_specs && decl_specs->specs[(int) ds_friend], is_declaration)); if (decl_specs) cp_parser_set_decl_spec_type (decl_specs, type_spec, /*user_defined_p=*/true); return type_spec; case RID_CONST: ds = ds_const; if (is_cv_qualifier) *is_cv_qualifier = true; break; case RID_VOLATILE: ds = ds_volatile; if (is_cv_qualifier) *is_cv_qualifier = true; break; case RID_RESTRICT: ds = ds_restrict; if (is_cv_qualifier) *is_cv_qualifier = true; break; case RID_COMPLEX: /* The `__complex__' keyword is a GNU extension. */ ds = ds_complex; break; default: break; } /* Handle simple keywords. */ if (ds != ds_last) { if (decl_specs) { ++decl_specs->specs[(int)ds]; decl_specs->any_specifiers_p = true; } return cp_lexer_consume_token (parser->lexer)->u.value; } /* If we do not already have a type-specifier, assume we are looking at a simple-type-specifier. */ type_spec = cp_parser_simple_type_specifier (parser, decl_specs, flags); /* If we didn't find a type-specifier, and a type-specifier was not optional in this context, issue an error message. */ if (!type_spec && !(flags & CP_PARSER_FLAGS_OPTIONAL)) { cp_parser_error (parser, "expected type specifier"); return error_mark_node; } return type_spec; } /* Parse a simple-type-specifier. simple-type-specifier: :: [opt] nested-name-specifier [opt] type-name :: [opt] nested-name-specifier template template-id char wchar_t bool short int long signed unsigned float double void C++0x Extension: simple-type-specifier: auto decltype ( expression ) GNU Extension: simple-type-specifier: __typeof__ unary-expression __typeof__ ( type-id ) Returns the indicated TYPE_DECL. If DECL_SPECS is not NULL, it is appropriately updated. */ static tree cp_parser_simple_type_specifier (cp_parser* parser, cp_decl_specifier_seq *decl_specs, cp_parser_flags flags) { tree type = NULL_TREE; cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If we're looking at a keyword, things are easy. */ switch (token->keyword) { case RID_CHAR: if (decl_specs) decl_specs->explicit_char_p = true; type = char_type_node; break; case RID_WCHAR: type = wchar_type_node; break; case RID_BOOL: type = boolean_type_node; break; case RID_SHORT: if (decl_specs) ++decl_specs->specs[(int) ds_short]; type = short_integer_type_node; break; case RID_INT: if (decl_specs) decl_specs->explicit_int_p = true; type = integer_type_node; break; case RID_LONG: if (decl_specs) ++decl_specs->specs[(int) ds_long]; type = long_integer_type_node; break; case RID_SIGNED: if (decl_specs) ++decl_specs->specs[(int) ds_signed]; type = integer_type_node; break; case RID_UNSIGNED: if (decl_specs) ++decl_specs->specs[(int) ds_unsigned]; type = unsigned_type_node; break; case RID_FLOAT: type = float_type_node; break; case RID_DOUBLE: type = double_type_node; break; case RID_VOID: type = void_type_node; break; case RID_AUTO: if (cxx_dialect != cxx98) { /* Consume the token. */ cp_lexer_consume_token (parser->lexer); /* We do not yet support the use of `auto' as a type-specifier. */ error ("C++0x % specifier not supported"); } break; case RID_DECLTYPE: /* Parse the `decltype' type. */ type = cp_parser_decltype (parser); if (decl_specs) cp_parser_set_decl_spec_type (decl_specs, type, /*user_defined_p=*/true); return type; case RID_TYPEOF: /* Consume the `typeof' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the operand to `typeof'. */ type = cp_parser_sizeof_operand (parser, RID_TYPEOF); /* If it is not already a TYPE, take its type. */ if (!TYPE_P (type)) type = finish_typeof (type); if (decl_specs) cp_parser_set_decl_spec_type (decl_specs, type, /*user_defined_p=*/true); return type; default: break; } /* If the type-specifier was for a built-in type, we're done. */ if (type) { tree id; /* Record the type. */ if (decl_specs && (token->keyword != RID_SIGNED && token->keyword != RID_UNSIGNED && token->keyword != RID_SHORT && token->keyword != RID_LONG)) cp_parser_set_decl_spec_type (decl_specs, type, /*user_defined=*/false); if (decl_specs) decl_specs->any_specifiers_p = true; /* Consume the token. */ id = cp_lexer_consume_token (parser->lexer)->u.value; /* There is no valid C++ program where a non-template type is followed by a "<". That usually indicates that the user thought that the type was a template. */ cp_parser_check_for_invalid_template_id (parser, type); return TYPE_NAME (type); } /* The type-specifier must be a user-defined type. */ if (!(flags & CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES)) { bool qualified_p; bool global_p; /* Don't gobble tokens or issue error messages if this is an optional type-specifier. */ if (flags & CP_PARSER_FLAGS_OPTIONAL) cp_parser_parse_tentatively (parser); /* Look for the optional `::' operator. */ global_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* Look for the nested-name specifier. */ qualified_p = (cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/false) != NULL_TREE); /* If we have seen a nested-name-specifier, and the next token is `template', then we are using the template-id production. */ if (parser->scope && cp_parser_optional_template_keyword (parser)) { /* Look for the template-id. */ type = cp_parser_template_id (parser, /*template_keyword_p=*/true, /*check_dependency_p=*/true, /*is_declaration=*/false); /* If the template-id did not name a type, we are out of luck. */ if (TREE_CODE (type) != TYPE_DECL) { cp_parser_error (parser, "expected template-id for type"); type = NULL_TREE; } } /* Otherwise, look for a type-name. */ else type = cp_parser_type_name (parser); /* Keep track of all name-lookups performed in class scopes. */ if (type && !global_p && !qualified_p && TREE_CODE (type) == TYPE_DECL && TREE_CODE (DECL_NAME (type)) == IDENTIFIER_NODE) maybe_note_name_used_in_class (DECL_NAME (type), type); /* If it didn't work out, we don't have a TYPE. */ if ((flags & CP_PARSER_FLAGS_OPTIONAL) && !cp_parser_parse_definitely (parser)) type = NULL_TREE; if (type && decl_specs) cp_parser_set_decl_spec_type (decl_specs, type, /*user_defined=*/true); } /* If we didn't get a type-name, issue an error message. */ if (!type && !(flags & CP_PARSER_FLAGS_OPTIONAL)) { cp_parser_error (parser, "expected type-name"); return error_mark_node; } /* There is no valid C++ program where a non-template type is followed by a "<". That usually indicates that the user thought that the type was a template. */ if (type && type != error_mark_node) { /* As a last-ditch effort, see if TYPE is an Objective-C type. If it is, then the '<'...'>' enclose protocol names rather than template arguments, and so everything is fine. */ if (c_dialect_objc () && (objc_is_id (type) || objc_is_class_name (type))) { tree protos = cp_parser_objc_protocol_refs_opt (parser); tree qual_type = objc_get_protocol_qualified_type (type, protos); /* Clobber the "unqualified" type previously entered into DECL_SPECS with the new, improved protocol-qualified version. */ if (decl_specs) decl_specs->type = qual_type; return qual_type; } cp_parser_check_for_invalid_template_id (parser, TREE_TYPE (type)); } return type; } /* Parse a type-name. type-name: class-name enum-name typedef-name enum-name: identifier typedef-name: identifier Returns a TYPE_DECL for the type. */ static tree cp_parser_type_name (cp_parser* parser) { tree type_decl; /* We can't know yet whether it is a class-name or not. */ cp_parser_parse_tentatively (parser); /* Try a class-name. */ type_decl = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, none_type, /*check_dependency_p=*/true, /*class_head_p=*/false, /*is_declaration=*/false); /* If it's not a class-name, keep looking. */ if (!cp_parser_parse_definitely (parser)) { /* It must be a typedef-name or an enum-name. */ return cp_parser_nonclass_name (parser); } return type_decl; } /* Parse a non-class type-name, that is, either an enum-name or a typedef-name. enum-name: identifier typedef-name: identifier Returns a TYPE_DECL for the type. */ static tree cp_parser_nonclass_name (cp_parser* parser) { tree type_decl; tree identifier; identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return error_mark_node; /* Look up the type-name. */ type_decl = cp_parser_lookup_name_simple (parser, identifier); if (TREE_CODE (type_decl) != TYPE_DECL && (objc_is_id (identifier) || objc_is_class_name (identifier))) { /* See if this is an Objective-C type. */ tree protos = cp_parser_objc_protocol_refs_opt (parser); tree type = objc_get_protocol_qualified_type (identifier, protos); if (type) type_decl = TYPE_NAME (type); } /* Issue an error if we did not find a type-name. */ if (TREE_CODE (type_decl) != TYPE_DECL) { if (!cp_parser_simulate_error (parser)) cp_parser_name_lookup_error (parser, identifier, type_decl, "is not a type"); return error_mark_node; } /* Remember that the name was used in the definition of the current class so that we can check later to see if the meaning would have been different after the class was entirely defined. */ else if (type_decl != error_mark_node && !parser->scope) maybe_note_name_used_in_class (identifier, type_decl); return type_decl; } /* Parse an elaborated-type-specifier. Note that the grammar given here incorporates the resolution to DR68. elaborated-type-specifier: class-key :: [opt] nested-name-specifier [opt] identifier class-key :: [opt] nested-name-specifier [opt] template [opt] template-id enum :: [opt] nested-name-specifier [opt] identifier typename :: [opt] nested-name-specifier identifier typename :: [opt] nested-name-specifier template [opt] template-id GNU extension: elaborated-type-specifier: class-key attributes :: [opt] nested-name-specifier [opt] identifier class-key attributes :: [opt] nested-name-specifier [opt] template [opt] template-id enum attributes :: [opt] nested-name-specifier [opt] identifier If IS_FRIEND is TRUE, then this elaborated-type-specifier is being declared `friend'. If IS_DECLARATION is TRUE, then this elaborated-type-specifier appears in a decl-specifiers-seq, i.e., something is being declared. Returns the TYPE specified. */ static tree cp_parser_elaborated_type_specifier (cp_parser* parser, bool is_friend, bool is_declaration) { enum tag_types tag_type; tree identifier; tree type = NULL_TREE; tree attributes = NULL_TREE; /* See if we're looking at the `enum' keyword. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_ENUM)) { /* Consume the `enum' token. */ cp_lexer_consume_token (parser->lexer); /* Remember that it's an enumeration type. */ tag_type = enum_type; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); } /* Or, it might be `typename'. */ else if (cp_lexer_next_token_is_keyword (parser->lexer, RID_TYPENAME)) { /* Consume the `typename' token. */ cp_lexer_consume_token (parser->lexer); /* Remember that it's a `typename' type. */ tag_type = typename_type; /* The `typename' keyword is only allowed in templates. */ if (!processing_template_decl) pedwarn ("using % outside of template"); } /* Otherwise it must be a class-key. */ else { tag_type = cp_parser_class_key (parser); if (tag_type == none_type) return error_mark_node; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); } /* Look for the `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name-specifier. */ if (tag_type == typename_type) { if (!cp_parser_nested_name_specifier (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, is_declaration)) return error_mark_node; } else /* Even though `typename' is not present, the proposed resolution to Core Issue 180 says that in `class A::B', `B' should be considered a type-name, even if `A' is dependent. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/true, /*check_dependency_p=*/true, /*type_p=*/true, is_declaration); /* For everything but enumeration types, consider a template-id. For an enumeration type, consider only a plain identifier. */ if (tag_type != enum_type) { bool template_p = false; tree decl; /* Allow the `template' keyword. */ template_p = cp_parser_optional_template_keyword (parser); /* If we didn't see `template', we don't know if there's a template-id or not. */ if (!template_p) cp_parser_parse_tentatively (parser); /* Parse the template-id. */ decl = cp_parser_template_id (parser, template_p, /*check_dependency_p=*/true, is_declaration); /* If we didn't find a template-id, look for an ordinary identifier. */ if (!template_p && !cp_parser_parse_definitely (parser)) ; /* If DECL is a TEMPLATE_ID_EXPR, and the `typename' keyword is in effect, then we must assume that, upon instantiation, the template will correspond to a class. */ else if (TREE_CODE (decl) == TEMPLATE_ID_EXPR && tag_type == typename_type) type = make_typename_type (parser->scope, decl, typename_type, /*complain=*/tf_error); else type = TREE_TYPE (decl); } if (!type) { identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) { parser->scope = NULL_TREE; return error_mark_node; } /* For a `typename', we needn't call xref_tag. */ if (tag_type == typename_type && TREE_CODE (parser->scope) != NAMESPACE_DECL) return cp_parser_make_typename_type (parser, parser->scope, identifier); /* Look up a qualified name in the usual way. */ if (parser->scope) { tree decl; tree ambiguous_decls; decl = cp_parser_lookup_name (parser, identifier, tag_type, /*is_template=*/false, /*is_namespace=*/false, /*check_dependency=*/true, &ambiguous_decls); /* If the lookup was ambiguous, an error will already have been issued. */ if (ambiguous_decls) return error_mark_node; /* If we are parsing friend declaration, DECL may be a TEMPLATE_DECL tree node here. However, we need to check whether this TEMPLATE_DECL results in valid code. Consider the following example: namespace N { template class C {}; } class X { template friend class N::C; // #1, valid code }; template class Y { friend class N::C; // #2, invalid code }; For both case #1 and #2, we arrive at a TEMPLATE_DECL after name lookup of `N::C'. We see that friend declaration must be template for the code to be valid. Note that processing_template_decl does not work here since it is always 1 for the above two cases. */ decl = (cp_parser_maybe_treat_template_as_class (decl, /*tag_name_p=*/is_friend && parser->num_template_parameter_lists)); if (TREE_CODE (decl) != TYPE_DECL) { cp_parser_diagnose_invalid_type_name (parser, parser->scope, identifier); return error_mark_node; } if (TREE_CODE (TREE_TYPE (decl)) != TYPENAME_TYPE) { bool allow_template = (parser->num_template_parameter_lists || DECL_SELF_REFERENCE_P (decl)); type = check_elaborated_type_specifier (tag_type, decl, allow_template); if (type == error_mark_node) return error_mark_node; } /* Forward declarations of nested types, such as class C1::C2; class C1::C2::C3; are invalid unless all components preceding the final '::' are complete. If all enclosing types are complete, these declarations become merely pointless. Invalid forward declarations of nested types are errors caught elsewhere in parsing. Those that are pointless arrive here. */ if (cp_parser_declares_only_class_p (parser) && !is_friend && !processing_explicit_instantiation) warning (0, "declaration %qD does not declare anything", decl); type = TREE_TYPE (decl); } else { /* An elaborated-type-specifier sometimes introduces a new type and sometimes names an existing type. Normally, the rule is that it introduces a new type only if there is not an existing type of the same name already in scope. For example, given: struct S {}; void f() { struct S s; } the `struct S' in the body of `f' is the same `struct S' as in the global scope; the existing definition is used. However, if there were no global declaration, this would introduce a new local class named `S'. An exception to this rule applies to the following code: namespace N { struct S; } Here, the elaborated-type-specifier names a new type unconditionally; even if there is already an `S' in the containing scope this declaration names a new type. This exception only applies if the elaborated-type-specifier forms the complete declaration: [class.name] A declaration consisting solely of `class-key identifier ;' is either a redeclaration of the name in the current scope or a forward declaration of the identifier as a class name. It introduces the name into the current scope. We are in this situation precisely when the next token is a `;'. An exception to the exception is that a `friend' declaration does *not* name a new type; i.e., given: struct S { friend struct T; }; `T' is not a new type in the scope of `S'. Also, `new struct S' or `sizeof (struct S)' never results in the definition of a new type; a new type can only be declared in a declaration context. */ tag_scope ts; bool template_p; if (is_friend) /* Friends have special name lookup rules. */ ts = ts_within_enclosing_non_class; else if (is_declaration && cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON)) /* This is a `class-key identifier ;' */ ts = ts_current; else ts = ts_global; template_p = (parser->num_template_parameter_lists && (cp_parser_next_token_starts_class_definition_p (parser) || cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON))); /* An unqualified name was used to reference this type, so there were no qualifying templates. */ if (!cp_parser_check_template_parameters (parser, /*num_templates=*/0)) return error_mark_node; type = xref_tag (tag_type, identifier, ts, template_p); } } if (type == error_mark_node) return error_mark_node; /* Allow attributes on forward declarations of classes. */ if (attributes) { if (TREE_CODE (type) == TYPENAME_TYPE) warning (OPT_Wattributes, "attributes ignored on uninstantiated type"); else if (tag_type != enum_type && CLASSTYPE_TEMPLATE_INSTANTIATION (type) && ! processing_explicit_instantiation) warning (OPT_Wattributes, "attributes ignored on template instantiation"); else if (is_declaration && cp_parser_declares_only_class_p (parser)) cplus_decl_attributes (&type, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE); else warning (OPT_Wattributes, "attributes ignored on elaborated-type-specifier that is not a forward declaration"); } if (tag_type != enum_type) cp_parser_check_class_key (tag_type, type); /* A "<" cannot follow an elaborated type specifier. If that happens, the user was probably trying to form a template-id. */ cp_parser_check_for_invalid_template_id (parser, type); return type; } /* Parse an enum-specifier. enum-specifier: enum identifier [opt] { enumerator-list [opt] } GNU Extensions: enum attributes[opt] identifier [opt] { enumerator-list [opt] } attributes[opt] Returns an ENUM_TYPE representing the enumeration, or NULL_TREE if the token stream isn't an enum-specifier after all. */ static tree cp_parser_enum_specifier (cp_parser* parser) { tree identifier; tree type; tree attributes; /* Parse tentatively so that we can back up if we don't find a enum-specifier. */ cp_parser_parse_tentatively (parser); /* Caller guarantees that the current token is 'enum', an identifier possibly follows, and the token after that is an opening brace. If we don't have an identifier, fabricate an anonymous name for the enumeration being defined. */ cp_lexer_consume_token (parser->lexer); attributes = cp_parser_attributes_opt (parser); if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) identifier = cp_parser_identifier (parser); else identifier = make_anon_name (); /* Look for the `{' but don't consume it yet. */ if (!cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) cp_parser_simulate_error (parser); if (!cp_parser_parse_definitely (parser)) return NULL_TREE; /* Issue an error message if type-definitions are forbidden here. */ if (!cp_parser_check_type_definition (parser)) type = error_mark_node; else /* Create the new type. We do this before consuming the opening brace so the enum will be recorded as being on the line of its tag (or the 'enum' keyword, if there is no tag). */ type = start_enum (identifier); /* Consume the opening brace. */ cp_lexer_consume_token (parser->lexer); if (type == error_mark_node) { cp_parser_skip_to_end_of_block_or_statement (parser); return error_mark_node; } /* If the next token is not '}', then there are some enumerators. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_BRACE)) cp_parser_enumerator_list (parser, type); /* Consume the final '}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); /* Look for trailing attributes to apply to this enumeration, and apply them if appropriate. */ if (cp_parser_allow_gnu_extensions_p (parser)) { tree trailing_attr = cp_parser_attributes_opt (parser); cplus_decl_attributes (&type, trailing_attr, (int) ATTR_FLAG_TYPE_IN_PLACE); } /* Finish up the enumeration. */ finish_enum (type); return type; } /* Parse an enumerator-list. The enumerators all have the indicated TYPE. enumerator-list: enumerator-definition enumerator-list , enumerator-definition */ static void cp_parser_enumerator_list (cp_parser* parser, tree type) { while (true) { /* Parse an enumerator-definition. */ cp_parser_enumerator_definition (parser, type); /* If the next token is not a ',', we've reached the end of the list. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Otherwise, consume the `,' and keep going. */ cp_lexer_consume_token (parser->lexer); /* If the next token is a `}', there is a trailing comma. */ if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_BRACE)) { if (pedantic && !in_system_header) pedwarn ("comma at end of enumerator list"); break; } } } /* Parse an enumerator-definition. The enumerator has the indicated TYPE. enumerator-definition: enumerator enumerator = constant-expression enumerator: identifier */ static void cp_parser_enumerator_definition (cp_parser* parser, tree type) { tree identifier; tree value; /* Look for the identifier. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return; /* If the next token is an '=', then there is an explicit value. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { /* Consume the `=' token. */ cp_lexer_consume_token (parser->lexer); /* Parse the value. */ value = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/false, NULL); } else value = NULL_TREE; /* Create the enumerator. */ build_enumerator (identifier, value, type); } /* Parse a namespace-name. namespace-name: original-namespace-name namespace-alias Returns the NAMESPACE_DECL for the namespace. */ static tree cp_parser_namespace_name (cp_parser* parser) { tree identifier; tree namespace_decl; /* Get the name of the namespace. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return error_mark_node; /* Look up the identifier in the currently active scope. Look only for namespaces, due to: [basic.lookup.udir] When looking up a namespace-name in a using-directive or alias definition, only namespace names are considered. And: [basic.lookup.qual] During the lookup of a name preceding the :: scope resolution operator, object, function, and enumerator names are ignored. (Note that cp_parser_class_or_namespace_name only calls this function if the token after the name is the scope resolution operator.) */ namespace_decl = cp_parser_lookup_name (parser, identifier, none_type, /*is_template=*/false, /*is_namespace=*/true, /*check_dependency=*/true, /*ambiguous_decls=*/NULL); /* If it's not a namespace, issue an error. */ if (namespace_decl == error_mark_node || TREE_CODE (namespace_decl) != NAMESPACE_DECL) { if (!cp_parser_uncommitted_to_tentative_parse_p (parser)) error ("%qD is not a namespace-name", identifier); cp_parser_error (parser, "expected namespace-name"); namespace_decl = error_mark_node; } return namespace_decl; } /* Parse a namespace-definition. namespace-definition: named-namespace-definition unnamed-namespace-definition named-namespace-definition: original-namespace-definition extension-namespace-definition original-namespace-definition: namespace identifier { namespace-body } extension-namespace-definition: namespace original-namespace-name { namespace-body } unnamed-namespace-definition: namespace { namespace-body } */ static void cp_parser_namespace_definition (cp_parser* parser) { tree identifier, attribs; bool has_visibility; bool is_inline; if (cp_lexer_next_token_is_keyword (parser->lexer, RID_INLINE)) { is_inline = true; cp_lexer_consume_token (parser->lexer); } else is_inline = false; /* Look for the `namespace' keyword. */ cp_parser_require_keyword (parser, RID_NAMESPACE, "`namespace'"); /* Get the name of the namespace. We do not attempt to distinguish between an original-namespace-definition and an extension-namespace-definition at this point. The semantic analysis routines are responsible for that. */ if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) identifier = cp_parser_identifier (parser); else identifier = NULL_TREE; /* Parse any specified attributes. */ attribs = cp_parser_attributes_opt (parser); /* Look for the `{' to start the namespace. */ cp_parser_require (parser, CPP_OPEN_BRACE, "`{'"); /* Start the namespace. */ push_namespace (identifier); /* "inline namespace" is equivalent to a stub namespace definition followed by a strong using directive. */ if (is_inline) { tree namespace = current_namespace; /* Set up namespace association. */ DECL_NAMESPACE_ASSOCIATIONS (namespace) = tree_cons (CP_DECL_CONTEXT (namespace), NULL_TREE, DECL_NAMESPACE_ASSOCIATIONS (namespace)); /* Import the contents of the inline namespace. */ pop_namespace (); do_using_directive (namespace); push_namespace (identifier); } has_visibility = handle_namespace_attrs (current_namespace, attribs); /* Parse the body of the namespace. */ cp_parser_namespace_body (parser); #ifdef HANDLE_PRAGMA_VISIBILITY if (has_visibility) pop_visibility (); #endif /* Finish the namespace. */ pop_namespace (); /* Look for the final `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } /* Parse a namespace-body. namespace-body: declaration-seq [opt] */ static void cp_parser_namespace_body (cp_parser* parser) { cp_parser_declaration_seq_opt (parser); } /* Parse a namespace-alias-definition. namespace-alias-definition: namespace identifier = qualified-namespace-specifier ; */ static void cp_parser_namespace_alias_definition (cp_parser* parser) { tree identifier; tree namespace_specifier; /* Look for the `namespace' keyword. */ cp_parser_require_keyword (parser, RID_NAMESPACE, "`namespace'"); /* Look for the identifier. */ identifier = cp_parser_identifier (parser); if (identifier == error_mark_node) return; /* Look for the `=' token. */ if (!cp_parser_uncommitted_to_tentative_parse_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) { error ("% definition is not allowed here"); /* Skip the definition. */ cp_lexer_consume_token (parser->lexer); if (cp_parser_skip_to_closing_brace (parser)) cp_lexer_consume_token (parser->lexer); return; } cp_parser_require (parser, CPP_EQ, "`='"); /* Look for the qualified-namespace-specifier. */ namespace_specifier = cp_parser_qualified_namespace_specifier (parser); /* Look for the `;' token. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); /* Register the alias in the symbol table. */ do_namespace_alias (identifier, namespace_specifier); } /* Parse a qualified-namespace-specifier. qualified-namespace-specifier: :: [opt] nested-name-specifier [opt] namespace-name Returns a NAMESPACE_DECL corresponding to the specified namespace. */ static tree cp_parser_qualified_namespace_specifier (cp_parser* parser) { /* Look for the optional `::'. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the optional nested-name-specifier. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); return cp_parser_namespace_name (parser); } /* Parse a using-declaration, or, if ACCESS_DECLARATION_P is true, an access declaration. using-declaration: using typename [opt] :: [opt] nested-name-specifier unqualified-id ; using :: unqualified-id ; access-declaration: qualified-id ; */ static bool cp_parser_using_declaration (cp_parser* parser, bool access_declaration_p) { cp_token *token; bool typename_p = false; bool global_scope_p; tree decl; tree identifier; tree qscope; if (access_declaration_p) cp_parser_parse_tentatively (parser); else { /* Look for the `using' keyword. */ cp_parser_require_keyword (parser, RID_USING, "`using'"); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* See if it's `typename'. */ if (token->keyword == RID_TYPENAME) { /* Remember that we've seen it. */ typename_p = true; /* Consume the `typename' token. */ cp_lexer_consume_token (parser->lexer); } } /* Look for the optional global scope qualification. */ global_scope_p = (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false) != NULL_TREE); /* If we saw `typename', or didn't see `::', then there must be a nested-name-specifier present. */ if (typename_p || !global_scope_p) qscope = cp_parser_nested_name_specifier (parser, typename_p, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); /* Otherwise, we could be in either of the two productions. In that case, treat the nested-name-specifier as optional. */ else qscope = cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); if (!qscope) qscope = global_namespace; if (access_declaration_p && cp_parser_error_occurred (parser)) /* Something has already gone wrong; there's no need to parse further. Since an error has occurred, the return value of cp_parser_parse_definitely will be false, as required. */ return cp_parser_parse_definitely (parser); /* Parse the unqualified-id. */ identifier = cp_parser_unqualified_id (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*declarator_p=*/true, /*optional_p=*/false); if (access_declaration_p) { if (cp_lexer_next_token_is_not (parser->lexer, CPP_SEMICOLON)) cp_parser_simulate_error (parser); if (!cp_parser_parse_definitely (parser)) return false; } /* The function we call to handle a using-declaration is different depending on what scope we are in. */ if (qscope == error_mark_node || identifier == error_mark_node) ; else if (TREE_CODE (identifier) != IDENTIFIER_NODE && TREE_CODE (identifier) != BIT_NOT_EXPR) /* [namespace.udecl] A using declaration shall not name a template-id. */ error ("a template-id may not appear in a using-declaration"); else { if (at_class_scope_p ()) { /* Create the USING_DECL. */ decl = do_class_using_decl (parser->scope, identifier); if (check_for_bare_parameter_packs (decl)) return false; else /* Add it to the list of members in this class. */ finish_member_declaration (decl); } else { decl = cp_parser_lookup_name_simple (parser, identifier); if (decl == error_mark_node) cp_parser_name_lookup_error (parser, identifier, decl, NULL); else if (check_for_bare_parameter_packs (decl)) return false; else if (!at_namespace_scope_p ()) do_local_using_decl (decl, qscope, identifier); else do_toplevel_using_decl (decl, qscope, identifier); } } /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); return true; } /* Parse a using-directive. using-directive: using namespace :: [opt] nested-name-specifier [opt] namespace-name ; */ static void cp_parser_using_directive (cp_parser* parser) { tree namespace_decl; tree attribs; /* Look for the `using' keyword. */ cp_parser_require_keyword (parser, RID_USING, "`using'"); /* And the `namespace' keyword. */ cp_parser_require_keyword (parser, RID_NAMESPACE, "`namespace'"); /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* And the optional nested-name-specifier. */ cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/true); /* Get the namespace being used. */ namespace_decl = cp_parser_namespace_name (parser); /* And any specified attributes. */ attribs = cp_parser_attributes_opt (parser); /* Update the symbol table. */ parse_using_directive (namespace_decl, attribs); /* Look for the final `;'. */ cp_parser_require (parser, CPP_SEMICOLON, "`;'"); } /* Parse an asm-definition. asm-definition: asm ( string-literal ) ; GNU Extension: asm-definition: asm volatile [opt] ( string-literal ) ; asm volatile [opt] ( string-literal : asm-operand-list [opt] ) ; asm volatile [opt] ( string-literal : asm-operand-list [opt] : asm-operand-list [opt] ) ; asm volatile [opt] ( string-literal : asm-operand-list [opt] : asm-operand-list [opt] : asm-operand-list [opt] ) ; */ static void cp_parser_asm_definition (cp_parser* parser) { tree string; tree outputs = NULL_TREE; tree inputs = NULL_TREE; tree clobbers = NULL_TREE; tree asm_stmt; bool volatile_p = false; bool extended_p = false; bool invalid_inputs_p = false; bool invalid_outputs_p = false; /* Look for the `asm' keyword. */ cp_parser_require_keyword (parser, RID_ASM, "`asm'"); /* See if the next token is `volatile'. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is_keyword (parser->lexer, RID_VOLATILE)) { /* Remember that we saw the `volatile' keyword. */ volatile_p = true; /* Consume the token. */ cp_lexer_consume_token (parser->lexer); } /* Look for the opening `('. */ if (!cp_parser_require (parser, CPP_OPEN_PAREN, "`('")) return; /* Look for the string. */ string = cp_parser_string_literal (parser, false, false); if (string == error_mark_node) { cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); return; } /* If we're allowing GNU extensions, check for the extended assembly syntax. Unfortunately, the `:' tokens need not be separated by a space in C, and so, for compatibility, we tolerate that here too. Doing that means that we have to treat the `::' operator as two `:' tokens. */ if (cp_parser_allow_gnu_extensions_p (parser) && parser->in_function_body && (cp_lexer_next_token_is (parser->lexer, CPP_COLON) || cp_lexer_next_token_is (parser->lexer, CPP_SCOPE))) { bool inputs_p = false; bool clobbers_p = false; /* The extended syntax was used. */ extended_p = true; /* Look for outputs. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COLON)) { /* Consume the `:'. */ cp_lexer_consume_token (parser->lexer); /* Parse the output-operands. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COLON) && cp_lexer_next_token_is_not (parser->lexer, CPP_SCOPE) && cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) outputs = cp_parser_asm_operand_list (parser); if (outputs == error_mark_node) invalid_outputs_p = true; } /* If the next token is `::', there are no outputs, and the next token is the beginning of the inputs. */ else if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) /* The inputs are coming next. */ inputs_p = true; /* Look for inputs. */ if (inputs_p || cp_lexer_next_token_is (parser->lexer, CPP_COLON)) { /* Consume the `:' or `::'. */ cp_lexer_consume_token (parser->lexer); /* Parse the output-operands. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COLON) && cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) inputs = cp_parser_asm_operand_list (parser); if (inputs == error_mark_node) invalid_inputs_p = true; } else if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) /* The clobbers are coming next. */ clobbers_p = true; /* Look for clobbers. */ if (clobbers_p || cp_lexer_next_token_is (parser->lexer, CPP_COLON)) { /* Consume the `:' or `::'. */ cp_lexer_consume_token (parser->lexer); /* Parse the clobbers. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_PAREN)) clobbers = cp_parser_asm_clobber_list (parser); } } /* Look for the closing `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) cp_parser_skip_to_closing_parenthesis (parser, true, false, /*consume_paren=*/true); cp_parser_require (parser, CPP_SEMICOLON, "`;'"); if (!invalid_inputs_p && !invalid_outputs_p) { /* Create the ASM_EXPR. */ if (parser->in_function_body) { asm_stmt = finish_asm_stmt (volatile_p, string, outputs, inputs, clobbers); /* If the extended syntax was not used, mark the ASM_EXPR. */ if (!extended_p) { tree temp = asm_stmt; if (TREE_CODE (temp) == CLEANUP_POINT_EXPR) temp = TREE_OPERAND (temp, 0); ASM_INPUT_P (temp) = 1; } } else cgraph_add_asm_node (string); } } /* Declarators [gram.dcl.decl] */ /* Parse an init-declarator. init-declarator: declarator initializer [opt] GNU Extension: init-declarator: declarator asm-specification [opt] attributes [opt] initializer [opt] function-definition: decl-specifier-seq [opt] declarator ctor-initializer [opt] function-body decl-specifier-seq [opt] declarator function-try-block GNU Extension: function-definition: __extension__ function-definition The DECL_SPECIFIERS apply to this declarator. Returns a representation of the entity declared. If MEMBER_P is TRUE, then this declarator appears in a class scope. The new DECL created by this declarator is returned. The CHECKS are access checks that should be performed once we know what entity is being declared (and, therefore, what classes have befriended it). If FUNCTION_DEFINITION_ALLOWED_P then we handle the declarator and for a function-definition here as well. If the declarator is a declarator for a function-definition, *FUNCTION_DEFINITION_P will be TRUE upon return. By that point, the function-definition will have been completely parsed. FUNCTION_DEFINITION_P may be NULL if FUNCTION_DEFINITION_ALLOWED_P is FALSE. */ static tree cp_parser_init_declarator (cp_parser* parser, cp_decl_specifier_seq *decl_specifiers, VEC (deferred_access_check,gc)* checks, bool function_definition_allowed_p, bool member_p, int declares_class_or_enum, bool* function_definition_p) { cp_token *token; cp_declarator *declarator; tree prefix_attributes; tree attributes; tree asm_specification; tree initializer; tree decl = NULL_TREE; tree scope; bool is_initialized; /* Only valid if IS_INITIALIZED is true. In that case, CPP_EQ if initialized with "= ..", CPP_OPEN_PAREN if initialized with "(...)". */ enum cpp_ttype initialization_kind; bool is_parenthesized_init = false; bool is_non_constant_init; int ctor_dtor_or_conv_p; bool friend_p; tree pushed_scope = NULL; /* Gather the attributes that were provided with the decl-specifiers. */ prefix_attributes = decl_specifiers->attributes; /* Assume that this is not the declarator for a function definition. */ if (function_definition_p) *function_definition_p = false; /* Defer access checks while parsing the declarator; we cannot know what names are accessible until we know what is being declared. */ resume_deferring_access_checks (); /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_NAMED, &ctor_dtor_or_conv_p, /*parenthesized_p=*/NULL, /*member_p=*/false); /* Gather up the deferred checks. */ stop_deferring_access_checks (); /* If the DECLARATOR was erroneous, there's no need to go further. */ if (declarator == cp_error_declarator) return error_mark_node; /* Check that the number of template-parameter-lists is OK. */ if (!cp_parser_check_declarator_template_parameters (parser, declarator)) return error_mark_node; if (declares_class_or_enum & 2) cp_parser_check_for_definition_in_return_type (declarator, decl_specifiers->type); /* Figure out what scope the entity declared by the DECLARATOR is located in. `grokdeclarator' sometimes changes the scope, so we compute it now. */ scope = get_scope_of_declarator (declarator); /* If we're allowing GNU extensions, look for an asm-specification and attributes. */ if (cp_parser_allow_gnu_extensions_p (parser)) { /* Look for an asm-specification. */ asm_specification = cp_parser_asm_specification_opt (parser); /* And attributes. */ attributes = cp_parser_attributes_opt (parser); } else { asm_specification = NULL_TREE; attributes = NULL_TREE; } /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check to see if the token indicates the start of a function-definition. */ if (cp_parser_token_starts_function_definition_p (token)) { if (!function_definition_allowed_p) { /* If a function-definition should not appear here, issue an error message. */ cp_parser_error (parser, "a function-definition is not allowed here"); return error_mark_node; } else { /* Neither attributes nor an asm-specification are allowed on a function-definition. */ if (asm_specification) error ("an asm-specification is not allowed on a function-definition"); if (attributes) error ("attributes are not allowed on a function-definition"); /* This is a function-definition. */ *function_definition_p = true; /* Parse the function definition. */ if (member_p) decl = cp_parser_save_member_function_body (parser, decl_specifiers, declarator, prefix_attributes); else decl = (cp_parser_function_definition_from_specifiers_and_declarator (parser, decl_specifiers, prefix_attributes, declarator)); return decl; } } /* [dcl.dcl] Only in function declarations for constructors, destructors, and type conversions can the decl-specifier-seq be omitted. We explicitly postpone this check past the point where we handle function-definitions because we tolerate function-definitions that are missing their return types in some modes. */ if (!decl_specifiers->any_specifiers_p && ctor_dtor_or_conv_p <= 0) { cp_parser_error (parser, "expected constructor, destructor, or type conversion"); return error_mark_node; } /* An `=' or an `(' indicates an initializer. */ if (token->type == CPP_EQ || token->type == CPP_OPEN_PAREN) { is_initialized = true; initialization_kind = token->type; } else { /* If the init-declarator isn't initialized and isn't followed by a `,' or `;', it's not a valid init-declarator. */ if (token->type != CPP_COMMA && token->type != CPP_SEMICOLON) { cp_parser_error (parser, "expected initializer"); return error_mark_node; } is_initialized = false; initialization_kind = CPP_EOF; } /* Because start_decl has side-effects, we should only call it if we know we're going ahead. By this point, we know that we cannot possibly be looking at any other construct. */ cp_parser_commit_to_tentative_parse (parser); /* If the decl specifiers were bad, issue an error now that we're sure this was intended to be a declarator. Then continue declaring the variable(s), as int, to try to cut down on further errors. */ if (decl_specifiers->any_specifiers_p && decl_specifiers->type == error_mark_node) { cp_parser_error (parser, "invalid type in declaration"); decl_specifiers->type = integer_type_node; } /* Check to see whether or not this declaration is a friend. */ friend_p = cp_parser_friend_p (decl_specifiers); /* Enter the newly declared entry in the symbol table. If we're processing a declaration in a class-specifier, we wait until after processing the initializer. */ if (!member_p) { if (parser->in_unbraced_linkage_specification_p) decl_specifiers->storage_class = sc_extern; decl = start_decl (declarator, decl_specifiers, is_initialized, attributes, prefix_attributes, &pushed_scope); } else if (scope) /* Enter the SCOPE. That way unqualified names appearing in the initializer will be looked up in SCOPE. */ pushed_scope = push_scope (scope); /* Perform deferred access control checks, now that we know in which SCOPE the declared entity resides. */ if (!member_p && decl) { tree saved_current_function_decl = NULL_TREE; /* If the entity being declared is a function, pretend that we are in its scope. If it is a `friend', it may have access to things that would not otherwise be accessible. */ if (TREE_CODE (decl) == FUNCTION_DECL) { saved_current_function_decl = current_function_decl; current_function_decl = decl; } /* Perform access checks for template parameters. */ cp_parser_perform_template_parameter_access_checks (checks); /* Perform the access control checks for the declarator and the the decl-specifiers. */ perform_deferred_access_checks (); /* Restore the saved value. */ if (TREE_CODE (decl) == FUNCTION_DECL) current_function_decl = saved_current_function_decl; } /* Parse the initializer. */ initializer = NULL_TREE; is_parenthesized_init = false; is_non_constant_init = true; if (is_initialized) { if (function_declarator_p (declarator)) { if (initialization_kind == CPP_EQ) initializer = cp_parser_pure_specifier (parser); else { /* If the declaration was erroneous, we don't really know what the user intended, so just silently consume the initializer. */ if (decl != error_mark_node) error ("initializer provided for function"); cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/false, /*consume_paren=*/true); } } else initializer = cp_parser_initializer (parser, &is_parenthesized_init, &is_non_constant_init); } /* The old parser allows attributes to appear after a parenthesized initializer. Mark Mitchell proposed removing this functionality on the GCC mailing lists on 2002-08-13. This parser accepts the attributes -- but ignores them. */ if (cp_parser_allow_gnu_extensions_p (parser) && is_parenthesized_init) if (cp_parser_attributes_opt (parser)) warning (OPT_Wattributes, "attributes after parenthesized initializer ignored"); /* For an in-class declaration, use `grokfield' to create the declaration. */ if (member_p) { if (pushed_scope) { pop_scope (pushed_scope); pushed_scope = false; } decl = grokfield (declarator, decl_specifiers, initializer, !is_non_constant_init, /*asmspec=*/NULL_TREE, prefix_attributes); if (decl && TREE_CODE (decl) == FUNCTION_DECL) cp_parser_save_default_args (parser, decl); } /* Finish processing the declaration. But, skip friend declarations. */ if (!friend_p && decl && decl != error_mark_node) { cp_finish_decl (decl, initializer, !is_non_constant_init, asm_specification, /* If the initializer is in parentheses, then this is a direct-initialization, which means that an `explicit' constructor is OK. Otherwise, an `explicit' constructor cannot be used. */ ((is_parenthesized_init || !is_initialized) ? 0 : LOOKUP_ONLYCONVERTING)); } else if ((cxx_dialect != cxx98) && friend_p && decl && TREE_CODE (decl) == FUNCTION_DECL) /* Core issue #226 (C++0x only): A default template-argument shall not be specified in a friend class template declaration. */ check_default_tmpl_args (decl, current_template_parms, /*is_primary=*/1, /*is_partial=*/0, /*is_friend_decl=*/1); if (!friend_p && pushed_scope) pop_scope (pushed_scope); return decl; } /* Parse a declarator. declarator: direct-declarator ptr-operator declarator abstract-declarator: ptr-operator abstract-declarator [opt] direct-abstract-declarator GNU Extensions: declarator: attributes [opt] direct-declarator attributes [opt] ptr-operator declarator abstract-declarator: attributes [opt] ptr-operator abstract-declarator [opt] attributes [opt] direct-abstract-declarator If CTOR_DTOR_OR_CONV_P is not NULL, *CTOR_DTOR_OR_CONV_P is used to detect constructor, destructor or conversion operators. It is set to -1 if the declarator is a name, and +1 if it is a function. Otherwise it is set to zero. Usually you just want to test for >0, but internally the negative value is used. (The reason for CTOR_DTOR_OR_CONV_P is that a declaration must have a decl-specifier-seq unless it declares a constructor, destructor, or conversion. It might seem that we could check this condition in semantic analysis, rather than parsing, but that makes it difficult to handle something like `f()'. We want to notice that there are no decl-specifiers, and therefore realize that this is an expression, not a declaration.) If PARENTHESIZED_P is non-NULL, *PARENTHESIZED_P is set to true iff the declarator is a direct-declarator of the form "(...)". MEMBER_P is true iff this declarator is a member-declarator. */ static cp_declarator * cp_parser_declarator (cp_parser* parser, cp_parser_declarator_kind dcl_kind, int* ctor_dtor_or_conv_p, bool* parenthesized_p, bool member_p) { cp_token *token; cp_declarator *declarator; enum tree_code code; cp_cv_quals cv_quals; tree class_type; tree attributes = NULL_TREE; /* Assume this is not a constructor, destructor, or type-conversion operator. */ if (ctor_dtor_or_conv_p) *ctor_dtor_or_conv_p = 0; if (cp_parser_allow_gnu_extensions_p (parser)) attributes = cp_parser_attributes_opt (parser); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check for the ptr-operator production. */ cp_parser_parse_tentatively (parser); /* Parse the ptr-operator. */ code = cp_parser_ptr_operator (parser, &class_type, &cv_quals); /* If that worked, then we have a ptr-operator. */ if (cp_parser_parse_definitely (parser)) { /* If a ptr-operator was found, then this declarator was not parenthesized. */ if (parenthesized_p) *parenthesized_p = true; /* The dependent declarator is optional if we are parsing an abstract-declarator. */ if (dcl_kind != CP_PARSER_DECLARATOR_NAMED) cp_parser_parse_tentatively (parser); /* Parse the dependent declarator. */ declarator = cp_parser_declarator (parser, dcl_kind, /*ctor_dtor_or_conv_p=*/NULL, /*parenthesized_p=*/NULL, /*member_p=*/false); /* If we are parsing an abstract-declarator, we must handle the case where the dependent declarator is absent. */ if (dcl_kind != CP_PARSER_DECLARATOR_NAMED && !cp_parser_parse_definitely (parser)) declarator = NULL; declarator = cp_parser_make_indirect_declarator (code, class_type, cv_quals, declarator); } /* Everything else is a direct-declarator. */ else { if (parenthesized_p) *parenthesized_p = cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN); declarator = cp_parser_direct_declarator (parser, dcl_kind, ctor_dtor_or_conv_p, member_p); } if (attributes && declarator && declarator != cp_error_declarator) declarator->attributes = attributes; return declarator; } /* Parse a direct-declarator or direct-abstract-declarator. direct-declarator: declarator-id direct-declarator ( parameter-declaration-clause ) cv-qualifier-seq [opt] exception-specification [opt] direct-declarator [ constant-expression [opt] ] ( declarator ) direct-abstract-declarator: direct-abstract-declarator [opt] ( parameter-declaration-clause ) cv-qualifier-seq [opt] exception-specification [opt] direct-abstract-declarator [opt] [ constant-expression [opt] ] ( abstract-declarator ) Returns a representation of the declarator. DCL_KIND is CP_PARSER_DECLARATOR_ABSTRACT, if we are parsing a direct-abstract-declarator. It is CP_PARSER_DECLARATOR_NAMED, if we are parsing a direct-declarator. It is CP_PARSER_DECLARATOR_EITHER, if we can accept either - in the case of ambiguity we prefer an abstract declarator, as per [dcl.ambig.res]. CTOR_DTOR_OR_CONV_P and MEMBER_P are as for cp_parser_declarator. */ static cp_declarator * cp_parser_direct_declarator (cp_parser* parser, cp_parser_declarator_kind dcl_kind, int* ctor_dtor_or_conv_p, bool member_p) { cp_token *token; cp_declarator *declarator = NULL; tree scope = NULL_TREE; bool saved_default_arg_ok_p = parser->default_arg_ok_p; bool saved_in_declarator_p = parser->in_declarator_p; bool first = true; tree pushed_scope = NULL_TREE; while (true) { /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); if (token->type == CPP_OPEN_PAREN) { /* This is either a parameter-declaration-clause, or a parenthesized declarator. When we know we are parsing a named declarator, it must be a parenthesized declarator if FIRST is true. For instance, `(int)' is a parameter-declaration-clause, with an omitted direct-abstract-declarator. But `((*))', is a parenthesized abstract declarator. Finally, when T is a template parameter `(T)' is a parameter-declaration-clause, and not a parenthesized named declarator. We first try and parse a parameter-declaration-clause, and then try a nested declarator (if FIRST is true). It is not an error for it not to be a parameter-declaration-clause, even when FIRST is false. Consider, int i (int); int i (3); The first is the declaration of a function while the second is a the definition of a variable, including its initializer. Having seen only the parenthesis, we cannot know which of these two alternatives should be selected. Even more complex are examples like: int i (int (a)); int i (int (3)); The former is a function-declaration; the latter is a variable initialization. Thus again, we try a parameter-declaration-clause, and if that fails, we back out and return. */ if (!first || dcl_kind != CP_PARSER_DECLARATOR_NAMED) { cp_parameter_declarator *params; unsigned saved_num_template_parameter_lists; /* In a member-declarator, the only valid interpretation of a parenthesis is the start of a parameter-declaration-clause. (It is invalid to initialize a static data member with a parenthesized initializer; only the "=" form of initialization is permitted.) */ if (!member_p) cp_parser_parse_tentatively (parser); /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); if (first) { /* If this is going to be an abstract declarator, we're in a declarator and we can't have default args. */ parser->default_arg_ok_p = false; parser->in_declarator_p = true; } /* Inside the function parameter list, surrounding template-parameter-lists do not apply. */ saved_num_template_parameter_lists = parser->num_template_parameter_lists; parser->num_template_parameter_lists = 0; /* Parse the parameter-declaration-clause. */ params = cp_parser_parameter_declaration_clause (parser); parser->num_template_parameter_lists = saved_num_template_parameter_lists; /* If all went well, parse the cv-qualifier-seq and the exception-specification. */ if (member_p || cp_parser_parse_definitely (parser)) { cp_cv_quals cv_quals; tree exception_specification; if (ctor_dtor_or_conv_p) *ctor_dtor_or_conv_p = *ctor_dtor_or_conv_p < 0; first = false; /* Consume the `)'. */ cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'"); /* Parse the cv-qualifier-seq. */ cv_quals = cp_parser_cv_qualifier_seq_opt (parser); /* And the exception-specification. */ exception_specification = cp_parser_exception_specification_opt (parser); /* Create the function-declarator. */ declarator = make_call_declarator (declarator, params, cv_quals, exception_specification); /* Any subsequent parameter lists are to do with return type, so are not those of the declared function. */ parser->default_arg_ok_p = false; /* Repeat the main loop. */ continue; } } /* If this is the first, we can try a parenthesized declarator. */ if (first) { bool saved_in_type_id_in_expr_p; parser->default_arg_ok_p = saved_default_arg_ok_p; parser->in_declarator_p = saved_in_declarator_p; /* Consume the `('. */ cp_lexer_consume_token (parser->lexer); /* Parse the nested declarator. */ saved_in_type_id_in_expr_p = parser->in_type_id_in_expr_p; parser->in_type_id_in_expr_p = true; declarator = cp_parser_declarator (parser, dcl_kind, ctor_dtor_or_conv_p, /*parenthesized_p=*/NULL, member_p); parser->in_type_id_in_expr_p = saved_in_type_id_in_expr_p; first = false; /* Expect a `)'. */ if (!cp_parser_require (parser, CPP_CLOSE_PAREN, "`)'")) declarator = cp_error_declarator; if (declarator == cp_error_declarator) break; goto handle_declarator; } /* Otherwise, we must be done. */ else break; } else if ((!first || dcl_kind != CP_PARSER_DECLARATOR_NAMED) && token->type == CPP_OPEN_SQUARE) { /* Parse an array-declarator. */ tree bounds; if (ctor_dtor_or_conv_p) *ctor_dtor_or_conv_p = 0; first = false; parser->default_arg_ok_p = false; parser->in_declarator_p = true; /* Consume the `['. */ cp_lexer_consume_token (parser->lexer); /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is `]', then there is no constant-expression. */ if (token->type != CPP_CLOSE_SQUARE) { bool non_constant_p; bounds = cp_parser_constant_expression (parser, /*allow_non_constant=*/true, &non_constant_p); if (!non_constant_p) bounds = fold_non_dependent_expr (bounds); /* Normally, the array bound must be an integral constant expression. However, as an extension, we allow VLAs in function scopes. */ else if (!parser->in_function_body) { error ("array bound is not an integer constant"); bounds = error_mark_node; } } else bounds = NULL_TREE; /* Look for the closing `]'. */ if (!cp_parser_require (parser, CPP_CLOSE_SQUARE, "`]'")) { declarator = cp_error_declarator; break; } declarator = make_array_declarator (declarator, bounds); } else if (first && dcl_kind != CP_PARSER_DECLARATOR_ABSTRACT) { tree qualifying_scope; tree unqualified_name; special_function_kind sfk; bool abstract_ok; bool pack_expansion_p = false; /* Parse a declarator-id */ abstract_ok = (dcl_kind == CP_PARSER_DECLARATOR_EITHER); if (abstract_ok) { cp_parser_parse_tentatively (parser); /* If we see an ellipsis, we should be looking at a parameter pack. */ if (token->type == CPP_ELLIPSIS) { /* Consume the `...' */ cp_lexer_consume_token (parser->lexer); pack_expansion_p = true; } } unqualified_name = cp_parser_declarator_id (parser, /*optional_p=*/abstract_ok); qualifying_scope = parser->scope; if (abstract_ok) { bool okay = false; if (!unqualified_name && pack_expansion_p) { /* Check whether an error occurred. */ okay = !cp_parser_error_occurred (parser); /* We already consumed the ellipsis to mark a parameter pack, but we have no way to report it, so abort the tentative parse. We will be exiting immediately anyway. */ cp_parser_abort_tentative_parse (parser); } else okay = cp_parser_parse_definitely (parser); if (!okay) unqualified_name = error_mark_node; else if (unqualified_name && (qualifying_scope || (TREE_CODE (unqualified_name) != IDENTIFIER_NODE))) { cp_parser_error (parser, "expected unqualified-id"); unqualified_name = error_mark_node; } } if (!unqualified_name) return NULL; if (unqualified_name == error_mark_node) { declarator = cp_error_declarator; pack_expansion_p = false; declarator->parameter_pack_p = false; break; } if (qualifying_scope && at_namespace_scope_p () && TREE_CODE (qualifying_scope) == TYPENAME_TYPE) { /* In the declaration of a member of a template class outside of the class itself, the SCOPE will sometimes be a TYPENAME_TYPE. For example, given: template int S::R::i = 3; the SCOPE will be a TYPENAME_TYPE for `S::R'. In this context, we must resolve S::R to an ordinary type, rather than a typename type. The reason we normally avoid resolving TYPENAME_TYPEs is that a specialization of `S' might render `S::R' not a type. However, if `S' is specialized, then this `i' will not be used, so there is no harm in resolving the types here. */ tree type; /* Resolve the TYPENAME_TYPE. */ type = resolve_typename_type (qualifying_scope, /*only_current_p=*/false); /* If that failed, the declarator is invalid. */ if (TREE_CODE (type) == TYPENAME_TYPE) error ("%<%T::%E%> is not a type", TYPE_CONTEXT (qualifying_scope), TYPE_IDENTIFIER (qualifying_scope)); qualifying_scope = type; } sfk = sfk_none; if (unqualified_name) { tree class_type; if (qualifying_scope && CLASS_TYPE_P (qualifying_scope)) class_type = qualifying_scope; else class_type = current_class_type; if (TREE_CODE (unqualified_name) == TYPE_DECL) { tree name_type = TREE_TYPE (unqualified_name); if (class_type && same_type_p (name_type, class_type)) { if (qualifying_scope && CLASSTYPE_USE_TEMPLATE (name_type)) { error ("invalid use of constructor as a template"); inform ("use %<%T::%D%> instead of %<%T::%D%> to " "name the constructor in a qualified name", class_type, DECL_NAME (TYPE_TI_TEMPLATE (class_type)), class_type, name_type); declarator = cp_error_declarator; break; } else unqualified_name = constructor_name (class_type); } else { /* We do not attempt to print the declarator here because we do not have enough information about its original syntactic form. */ cp_parser_error (parser, "invalid declarator"); declarator = cp_error_declarator; break; } } if (class_type) { if (TREE_CODE (unqualified_name) == BIT_NOT_EXPR) sfk = sfk_destructor; else if (IDENTIFIER_TYPENAME_P (unqualified_name)) sfk = sfk_conversion; else if (/* There's no way to declare a constructor for an anonymous type, even if the type got a name for linkage purposes. */ !TYPE_WAS_ANONYMOUS (class_type) && constructor_name_p (unqualified_name, class_type)) { unqualified_name = constructor_name (class_type); sfk = sfk_constructor; } if (ctor_dtor_or_conv_p && sfk != sfk_none) *ctor_dtor_or_conv_p = -1; } } declarator = make_id_declarator (qualifying_scope, unqualified_name, sfk); declarator->id_loc = token->location; declarator->parameter_pack_p = pack_expansion_p; if (pack_expansion_p) maybe_warn_variadic_templates (); handle_declarator:; scope = get_scope_of_declarator (declarator); if (scope) /* Any names that appear after the declarator-id for a member are looked up in the containing scope. */ pushed_scope = push_scope (scope); parser->in_declarator_p = true; if ((ctor_dtor_or_conv_p && *ctor_dtor_or_conv_p) || (declarator && declarator->kind == cdk_id)) /* Default args are only allowed on function declarations. */ parser->default_arg_ok_p = saved_default_arg_ok_p; else parser->default_arg_ok_p = false; first = false; } /* We're done. */ else break; } /* For an abstract declarator, we might wind up with nothing at this point. That's an error; the declarator is not optional. */ if (!declarator) cp_parser_error (parser, "expected declarator"); /* If we entered a scope, we must exit it now. */ if (pushed_scope) pop_scope (pushed_scope); parser->default_arg_ok_p = saved_default_arg_ok_p; parser->in_declarator_p = saved_in_declarator_p; return declarator; } /* Parse a ptr-operator. ptr-operator: * cv-qualifier-seq [opt] & :: [opt] nested-name-specifier * cv-qualifier-seq [opt] GNU Extension: ptr-operator: & cv-qualifier-seq [opt] Returns INDIRECT_REF if a pointer, or pointer-to-member, was used. Returns ADDR_EXPR if a reference was used, or NON_LVALUE_EXPR for an rvalue reference. In the case of a pointer-to-member, *TYPE is filled in with the TYPE containing the member. *CV_QUALS is filled in with the cv-qualifier-seq, or TYPE_UNQUALIFIED, if there are no cv-qualifiers. Returns ERROR_MARK if an error occurred. Note that the tree codes returned by this function have nothing to do with the types of trees that will be eventually be created to represent the pointer or reference type being parsed. They are just constants with suggestive names. */ static enum tree_code cp_parser_ptr_operator (cp_parser* parser, tree* type, cp_cv_quals *cv_quals) { enum tree_code code = ERROR_MARK; cp_token *token; /* Assume that it's not a pointer-to-member. */ *type = NULL_TREE; /* And that there are no cv-qualifiers. */ *cv_quals = TYPE_UNQUALIFIED; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `*', `&' or `&&' we have a pointer or reference. */ if (token->type == CPP_MULT) code = INDIRECT_REF; else if (token->type == CPP_AND) code = ADDR_EXPR; else if ((cxx_dialect != cxx98) && token->type == CPP_AND_AND) /* C++0x only */ code = NON_LVALUE_EXPR; if (code != ERROR_MARK) { /* Consume the `*', `&' or `&&'. */ cp_lexer_consume_token (parser->lexer); /* A `*' can be followed by a cv-qualifier-seq, and so can a `&', if we are allowing GNU extensions. (The only qualifier that can legally appear after `&' is `restrict', but that is enforced during semantic analysis. */ if (code == INDIRECT_REF || cp_parser_allow_gnu_extensions_p (parser)) *cv_quals = cp_parser_cv_qualifier_seq_opt (parser); } else { /* Try the pointer-to-member case. */ cp_parser_parse_tentatively (parser); /* Look for the optional `::' operator. */ cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false); /* Look for the nested-name specifier. */ cp_parser_nested_name_specifier (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/true, /*type_p=*/false, /*is_declaration=*/false); /* If we found it, and the next token is a `*', then we are indeed looking at a pointer-to-member operator. */ if (!cp_parser_error_occurred (parser) && cp_parser_require (parser, CPP_MULT, "`*'")) { /* Indicate that the `*' operator was used. */ code = INDIRECT_REF; if (TREE_CODE (parser->scope) == NAMESPACE_DECL) error ("%qD is a namespace", parser->scope); else { /* The type of which the member is a member is given by the current SCOPE. */ *type = parser->scope; /* The next name will not be qualified. */ parser->scope = NULL_TREE; parser->qualifying_scope = NULL_TREE; parser->object_scope = NULL_TREE; /* Look for the optional cv-qualifier-seq. */ *cv_quals = cp_parser_cv_qualifier_seq_opt (parser); } } /* If that didn't work we don't have a ptr-operator. */ if (!cp_parser_parse_definitely (parser)) cp_parser_error (parser, "expected ptr-operator"); } return code; } /* Parse an (optional) cv-qualifier-seq. cv-qualifier-seq: cv-qualifier cv-qualifier-seq [opt] cv-qualifier: const volatile GNU Extension: cv-qualifier: __restrict__ Returns a bitmask representing the cv-qualifiers. */ static cp_cv_quals cp_parser_cv_qualifier_seq_opt (cp_parser* parser) { cp_cv_quals cv_quals = TYPE_UNQUALIFIED; while (true) { cp_token *token; cp_cv_quals cv_qualifier; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* See if it's a cv-qualifier. */ switch (token->keyword) { case RID_CONST: cv_qualifier = TYPE_QUAL_CONST; break; case RID_VOLATILE: cv_qualifier = TYPE_QUAL_VOLATILE; break; case RID_RESTRICT: cv_qualifier = TYPE_QUAL_RESTRICT; break; default: cv_qualifier = TYPE_UNQUALIFIED; break; } if (!cv_qualifier) break; if (cv_quals & cv_qualifier) { error ("duplicate cv-qualifier"); cp_lexer_purge_token (parser->lexer); } else { cp_lexer_consume_token (parser->lexer); cv_quals |= cv_qualifier; } } return cv_quals; } /* Parse a declarator-id. declarator-id: id-expression :: [opt] nested-name-specifier [opt] type-name In the `id-expression' case, the value returned is as for cp_parser_id_expression if the id-expression was an unqualified-id. If the id-expression was a qualified-id, then a SCOPE_REF is returned. The first operand is the scope (either a NAMESPACE_DECL or TREE_TYPE), but the second is still just a representation of an unqualified-id. */ static tree cp_parser_declarator_id (cp_parser* parser, bool optional_p) { tree id; /* The expression must be an id-expression. Assume that qualified names are the names of types so that: template int S::R::i = 3; will work; we must treat `S::R' as the name of a type. Similarly, assume that qualified names are templates, where required, so that: template int S::R::i = 3; will work, too. */ id = cp_parser_id_expression (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/false, /*template_p=*/NULL, /*declarator_p=*/true, optional_p); if (id && BASELINK_P (id)) id = BASELINK_FUNCTIONS (id); return id; } /* Parse a type-id. type-id: type-specifier-seq abstract-declarator [opt] Returns the TYPE specified. */ static tree cp_parser_type_id (cp_parser* parser) { cp_decl_specifier_seq type_specifier_seq; cp_declarator *abstract_declarator; /* Parse the type-specifier-seq. */ cp_parser_type_specifier_seq (parser, /*is_condition=*/false, &type_specifier_seq); if (type_specifier_seq.type == error_mark_node) return error_mark_node; /* There might or might not be an abstract declarator. */ cp_parser_parse_tentatively (parser); /* Look for the declarator. */ abstract_declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_ABSTRACT, NULL, /*parenthesized_p=*/NULL, /*member_p=*/false); /* Check to see if there really was a declarator. */ if (!cp_parser_parse_definitely (parser)) abstract_declarator = NULL; return groktypename (&type_specifier_seq, abstract_declarator); } /* Parse a type-specifier-seq. type-specifier-seq: type-specifier type-specifier-seq [opt] GNU extension: type-specifier-seq: attributes type-specifier-seq [opt] If IS_CONDITION is true, we are at the start of a "condition", e.g., we've just seen "if (". Sets *TYPE_SPECIFIER_SEQ to represent the sequence. */ static void cp_parser_type_specifier_seq (cp_parser* parser, bool is_condition, cp_decl_specifier_seq *type_specifier_seq) { bool seen_type_specifier = false; cp_parser_flags flags = CP_PARSER_FLAGS_OPTIONAL; /* Clear the TYPE_SPECIFIER_SEQ. */ clear_decl_specs (type_specifier_seq); /* Parse the type-specifiers and attributes. */ while (true) { tree type_specifier; bool is_cv_qualifier; /* Check for attributes first. */ if (cp_lexer_next_token_is_keyword (parser->lexer, RID_ATTRIBUTE)) { type_specifier_seq->attributes = chainon (type_specifier_seq->attributes, cp_parser_attributes_opt (parser)); continue; } /* Look for the type-specifier. */ type_specifier = cp_parser_type_specifier (parser, flags, type_specifier_seq, /*is_declaration=*/false, NULL, &is_cv_qualifier); if (!type_specifier) { /* If the first type-specifier could not be found, this is not a type-specifier-seq at all. */ if (!seen_type_specifier) { cp_parser_error (parser, "expected type-specifier"); type_specifier_seq->type = error_mark_node; return; } /* If subsequent type-specifiers could not be found, the type-specifier-seq is complete. */ break; } seen_type_specifier = true; /* The standard says that a condition can be: type-specifier-seq declarator = assignment-expression However, given: struct S {}; if (int S = ...) we should treat the "S" as a declarator, not as a type-specifier. The standard doesn't say that explicitly for type-specifier-seq, but it does say that for decl-specifier-seq in an ordinary declaration. Perhaps it would be clearer just to allow a decl-specifier-seq here, and then add a semantic restriction that if any decl-specifiers that are not type-specifiers appear, the program is invalid. */ if (is_condition && !is_cv_qualifier) flags |= CP_PARSER_FLAGS_NO_USER_DEFINED_TYPES; } cp_parser_check_decl_spec (type_specifier_seq); } /* Parse a parameter-declaration-clause. parameter-declaration-clause: parameter-declaration-list [opt] ... [opt] parameter-declaration-list , ... Returns a representation for the parameter declarations. A return value of NULL indicates a parameter-declaration-clause consisting only of an ellipsis. */ static cp_parameter_declarator * cp_parser_parameter_declaration_clause (cp_parser* parser) { cp_parameter_declarator *parameters; cp_token *token; bool ellipsis_p; bool is_error; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Check for trivial parameter-declaration-clauses. */ if (token->type == CPP_ELLIPSIS) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); return NULL; } else if (token->type == CPP_CLOSE_PAREN) /* There are no parameters. */ { #ifndef NO_IMPLICIT_EXTERN_C if (in_system_header && current_class_type == NULL && current_lang_name == lang_name_c) return NULL; else #endif return no_parameters; } /* Check for `(void)', too, which is a special case. */ else if (token->keyword == RID_VOID && (cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_CLOSE_PAREN)) { /* Consume the `void' token. */ cp_lexer_consume_token (parser->lexer); /* There are no parameters. */ return no_parameters; } /* Parse the parameter-declaration-list. */ parameters = cp_parser_parameter_declaration_list (parser, &is_error); /* If a parse error occurred while parsing the parameter-declaration-list, then the entire parameter-declaration-clause is erroneous. */ if (is_error) return NULL; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If it's a `,', the clause should terminate with an ellipsis. */ if (token->type == CPP_COMMA) { /* Consume the `,'. */ cp_lexer_consume_token (parser->lexer); /* Expect an ellipsis. */ ellipsis_p = (cp_parser_require (parser, CPP_ELLIPSIS, "`...'") != NULL); } /* It might also be `...' if the optional trailing `,' was omitted. */ else if (token->type == CPP_ELLIPSIS) { /* Consume the `...' token. */ cp_lexer_consume_token (parser->lexer); /* And remember that we saw it. */ ellipsis_p = true; } else ellipsis_p = false; /* Finish the parameter list. */ if (parameters && ellipsis_p) parameters->ellipsis_p = true; return parameters; } /* Parse a parameter-declaration-list. parameter-declaration-list: parameter-declaration parameter-declaration-list , parameter-declaration Returns a representation of the parameter-declaration-list, as for cp_parser_parameter_declaration_clause. However, the `void_list_node' is never appended to the list. Upon return, *IS_ERROR will be true iff an error occurred. */ static cp_parameter_declarator * cp_parser_parameter_declaration_list (cp_parser* parser, bool *is_error) { cp_parameter_declarator *parameters = NULL; cp_parameter_declarator **tail = ¶meters; bool saved_in_unbraced_linkage_specification_p; /* Assume all will go well. */ *is_error = false; /* The special considerations that apply to a function within an unbraced linkage specifications do not apply to the parameters to the function. */ saved_in_unbraced_linkage_specification_p = parser->in_unbraced_linkage_specification_p; parser->in_unbraced_linkage_specification_p = false; /* Look for more parameters. */ while (true) { cp_parameter_declarator *parameter; bool parenthesized_p; /* Parse the parameter. */ parameter = cp_parser_parameter_declaration (parser, /*template_parm_p=*/false, &parenthesized_p); /* If a parse error occurred parsing the parameter declaration, then the entire parameter-declaration-list is erroneous. */ if (!parameter) { *is_error = true; parameters = NULL; break; } /* Add the new parameter to the list. */ *tail = parameter; tail = ¶meter->next; /* Peek at the next token. */ if (cp_lexer_next_token_is (parser->lexer, CPP_CLOSE_PAREN) || cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS) /* These are for Objective-C++ */ || cp_lexer_next_token_is (parser->lexer, CPP_SEMICOLON) || cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE)) /* The parameter-declaration-list is complete. */ break; else if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) { cp_token *token; /* Peek at the next token. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); /* If it's an ellipsis, then the list is complete. */ if (token->type == CPP_ELLIPSIS) break; /* Otherwise, there must be more parameters. Consume the `,'. */ cp_lexer_consume_token (parser->lexer); /* When parsing something like: int i(float f, double d) we can tell after seeing the declaration for "f" that we are not looking at an initialization of a variable "i", but rather at the declaration of a function "i". Due to the fact that the parsing of template arguments (as specified to a template-id) requires backtracking we cannot use this technique when inside a template argument list. */ if (!parser->in_template_argument_list_p && !parser->in_type_id_in_expr_p && cp_parser_uncommitted_to_tentative_parse_p (parser) /* However, a parameter-declaration of the form "foat(f)" (which is a valid declaration of a parameter "f") can also be interpreted as an expression (the conversion of "f" to "float"). */ && !parenthesized_p) cp_parser_commit_to_tentative_parse (parser); } else { cp_parser_error (parser, "expected %<,%> or %<...%>"); if (!cp_parser_uncommitted_to_tentative_parse_p (parser)) cp_parser_skip_to_closing_parenthesis (parser, /*recovering=*/true, /*or_comma=*/false, /*consume_paren=*/false); break; } } parser->in_unbraced_linkage_specification_p = saved_in_unbraced_linkage_specification_p; return parameters; } /* Parse a parameter declaration. parameter-declaration: decl-specifier-seq ... [opt] declarator decl-specifier-seq declarator = assignment-expression decl-specifier-seq ... [opt] abstract-declarator [opt] decl-specifier-seq abstract-declarator [opt] = assignment-expression If TEMPLATE_PARM_P is TRUE, then this parameter-declaration declares a template parameter. (In that case, a non-nested `>' token encountered during the parsing of the assignment-expression is not interpreted as a greater-than operator.) Returns a representation of the parameter, or NULL if an error occurs. If PARENTHESIZED_P is non-NULL, *PARENTHESIZED_P is set to true iff the declarator is of the form "(p)". */ static cp_parameter_declarator * cp_parser_parameter_declaration (cp_parser *parser, bool template_parm_p, bool *parenthesized_p) { int declares_class_or_enum; bool greater_than_is_operator_p; cp_decl_specifier_seq decl_specifiers; cp_declarator *declarator; tree default_argument; cp_token *token; const char *saved_message; /* In a template parameter, `>' is not an operator. [temp.param] When parsing a default template-argument for a non-type template-parameter, the first non-nested `>' is taken as the end of the template parameter-list rather than a greater-than operator. */ greater_than_is_operator_p = !template_parm_p; /* Type definitions may not appear in parameter types. */ saved_message = parser->type_definition_forbidden_message; parser->type_definition_forbidden_message = "types may not be defined in parameter types"; /* Parse the declaration-specifiers. */ cp_parser_decl_specifier_seq (parser, CP_PARSER_FLAGS_NONE, &decl_specifiers, &declares_class_or_enum); /* If an error occurred, there's no reason to attempt to parse the rest of the declaration. */ if (cp_parser_error_occurred (parser)) { parser->type_definition_forbidden_message = saved_message; return NULL; } /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* If the next token is a `)', `,', `=', `>', or `...', then there is no declarator. However, when variadic templates are enabled, there may be a declarator following `...'. */ if (token->type == CPP_CLOSE_PAREN || token->type == CPP_COMMA || token->type == CPP_EQ || token->type == CPP_GREATER) { declarator = NULL; if (parenthesized_p) *parenthesized_p = false; } /* Otherwise, there should be a declarator. */ else { bool saved_default_arg_ok_p = parser->default_arg_ok_p; parser->default_arg_ok_p = false; /* After seeing a decl-specifier-seq, if the next token is not a "(", there is no possibility that the code is a valid expression. Therefore, if parsing tentatively, we commit at this point. */ if (!parser->in_template_argument_list_p /* In an expression context, having seen: (int((char ... we cannot be sure whether we are looking at a function-type (taking a "char" as a parameter) or a cast of some object of type "char" to "int". */ && !parser->in_type_id_in_expr_p && cp_parser_uncommitted_to_tentative_parse_p (parser) && cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_PAREN)) cp_parser_commit_to_tentative_parse (parser); /* Parse the declarator. */ declarator = cp_parser_declarator (parser, CP_PARSER_DECLARATOR_EITHER, /*ctor_dtor_or_conv_p=*/NULL, parenthesized_p, /*member_p=*/false); parser->default_arg_ok_p = saved_default_arg_ok_p; /* After the declarator, allow more attributes. */ decl_specifiers.attributes = chainon (decl_specifiers.attributes, cp_parser_attributes_opt (parser)); } /* If the next token is an ellipsis, and we have not seen a declarator name, and the type of the declarator contains parameter packs but it is not a TYPE_PACK_EXPANSION, then we actually have a parameter pack expansion expression. Otherwise, leave the ellipsis for a C-style variadic function. */ token = cp_lexer_peek_token (parser->lexer); if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { tree type = decl_specifiers.type; if (type && DECL_P (type)) type = TREE_TYPE (type); if (type && TREE_CODE (type) != TYPE_PACK_EXPANSION && declarator_can_be_parameter_pack (declarator) && (!declarator || !declarator->parameter_pack_p) && uses_parameter_packs (type)) { /* Consume the `...'. */ cp_lexer_consume_token (parser->lexer); maybe_warn_variadic_templates (); /* Build a pack expansion type */ if (declarator) declarator->parameter_pack_p = true; else decl_specifiers.type = make_pack_expansion (type); } } /* The restriction on defining new types applies only to the type of the parameter, not to the default argument. */ parser->type_definition_forbidden_message = saved_message; /* If the next token is `=', then process a default argument. */ if (cp_lexer_next_token_is (parser->lexer, CPP_EQ)) { /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* If we are defining a class, then the tokens that make up the default argument must be saved and processed later. */ if (!template_parm_p && at_class_scope_p () && TYPE_BEING_DEFINED (current_class_type)) { unsigned depth = 0; cp_token *first_token; cp_token *token; /* Add tokens until we have processed the entire default argument. We add the range [first_token, token). */ first_token = cp_lexer_peek_token (parser->lexer); while (true) { bool done = false; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* What we do depends on what token we have. */ switch (token->type) { /* In valid code, a default argument must be immediately followed by a `,' `)', or `...'. */ case CPP_COMMA: case CPP_CLOSE_PAREN: case CPP_ELLIPSIS: /* If we run into a non-nested `;', `}', or `]', then the code is invalid -- but the default argument is certainly over. */ case CPP_SEMICOLON: case CPP_CLOSE_BRACE: case CPP_CLOSE_SQUARE: if (depth == 0) done = true; /* Update DEPTH, if necessary. */ else if (token->type == CPP_CLOSE_PAREN || token->type == CPP_CLOSE_BRACE || token->type == CPP_CLOSE_SQUARE) --depth; break; case CPP_OPEN_PAREN: case CPP_OPEN_SQUARE: case CPP_OPEN_BRACE: ++depth; break; case CPP_RSHIFT: if (cxx_dialect == cxx98) break; /* Fall through for C++0x, which treats the `>>' operator like two `>' tokens in certain cases. */ case CPP_GREATER: /* If we see a non-nested `>', and `>' is not an operator, then it marks the end of the default argument. */ if (!depth && !greater_than_is_operator_p) done = true; break; /* If we run out of tokens, issue an error message. */ case CPP_EOF: case CPP_PRAGMA_EOL: error ("file ends in default argument"); done = true; break; case CPP_NAME: case CPP_SCOPE: /* In these cases, we should look for template-ids. For example, if the default argument is `X()', we need to do name lookup to figure out whether or not `X' is a template; if so, the `,' does not end the default argument. That is not yet done. */ break; default: break; } /* If we've reached the end, stop. */ if (done) break; /* Add the token to the token block. */ token = cp_lexer_consume_token (parser->lexer); } /* Create a DEFAULT_ARG to represent the unparsed default argument. */ default_argument = make_node (DEFAULT_ARG); DEFARG_TOKENS (default_argument) = cp_token_cache_new (first_token, token); DEFARG_INSTANTIATIONS (default_argument) = NULL; } /* Outside of a class definition, we can just parse the assignment-expression. */ else default_argument = cp_parser_default_argument (parser, template_parm_p); if (!parser->default_arg_ok_p) { if (!flag_pedantic_errors) warning (0, "deprecated use of default argument for parameter of non-function"); else { error ("default arguments are only permitted for function parameters"); default_argument = NULL_TREE; } } else if ((declarator && declarator->parameter_pack_p) || (decl_specifiers.type && PACK_EXPANSION_P (decl_specifiers.type))) { const char* kind = template_parm_p? "template " : ""; /* Find the name of the parameter pack. */ cp_declarator *id_declarator = declarator; while (id_declarator && id_declarator->kind != cdk_id) id_declarator = id_declarator->declarator; if (id_declarator && id_declarator->kind == cdk_id) error ("%sparameter pack %qD cannot have a default argument", kind, id_declarator->u.id.unqualified_name); else error ("%sparameter pack cannot have a default argument", kind); default_argument = NULL_TREE; } } else default_argument = NULL_TREE; return make_parameter_declarator (&decl_specifiers, declarator, default_argument); } /* Parse a default argument and return it. TEMPLATE_PARM_P is true if this is a default argument for a non-type template parameter. */ static tree cp_parser_default_argument (cp_parser *parser, bool template_parm_p) { tree default_argument = NULL_TREE; bool saved_greater_than_is_operator_p; bool saved_local_variables_forbidden_p; /* Make sure that PARSER->GREATER_THAN_IS_OPERATOR_P is set correctly. */ saved_greater_than_is_operator_p = parser->greater_than_is_operator_p; parser->greater_than_is_operator_p = !template_parm_p; /* Local variable names (and the `this' keyword) may not appear in a default argument. */ saved_local_variables_forbidden_p = parser->local_variables_forbidden_p; parser->local_variables_forbidden_p = true; /* The default argument expression may cause implicitly defined member functions to be synthesized, which will result in garbage collection. We must treat this situation as if we were within the body of function so as to avoid collecting live data on the stack. */ ++function_depth; /* Parse the assignment-expression. */ if (template_parm_p) push_deferring_access_checks (dk_no_deferred); default_argument = cp_parser_assignment_expression (parser, /*cast_p=*/false); if (template_parm_p) pop_deferring_access_checks (); /* Restore saved state. */ --function_depth; parser->greater_than_is_operator_p = saved_greater_than_is_operator_p; parser->local_variables_forbidden_p = saved_local_variables_forbidden_p; return default_argument; } /* Parse a function-body. function-body: compound_statement */ static void cp_parser_function_body (cp_parser *parser) { cp_parser_compound_statement (parser, NULL, false); } /* Parse a ctor-initializer-opt followed by a function-body. Return true if a ctor-initializer was present. */ static bool cp_parser_ctor_initializer_opt_and_function_body (cp_parser *parser) { tree body; bool ctor_initializer_p; /* Begin the function body. */ body = begin_function_body (); /* Parse the optional ctor-initializer. */ ctor_initializer_p = cp_parser_ctor_initializer_opt (parser); /* Parse the function-body. */ cp_parser_function_body (parser); /* Finish the function body. */ finish_function_body (body); return ctor_initializer_p; } /* Parse an initializer. initializer: = initializer-clause ( expression-list ) Returns an expression representing the initializer. If no initializer is present, NULL_TREE is returned. *IS_PARENTHESIZED_INIT is set to TRUE if the `( expression-list )' production is used, and zero otherwise. *IS_PARENTHESIZED_INIT is set to FALSE if there is no initializer present. If there is an initializer, and it is not a constant-expression, *NON_CONSTANT_P is set to true; otherwise it is set to false. */ static tree cp_parser_initializer (cp_parser* parser, bool* is_parenthesized_init, bool* non_constant_p) { cp_token *token; tree init; /* Peek at the next token. */ token = cp_lexer_peek_token (parser->lexer); /* Let our caller know whether or not this initializer was parenthesized. */ *is_parenthesized_init = (token->type == CPP_OPEN_PAREN); /* Assume that the initializer is constant. */ *non_constant_p = false; if (token->type == CPP_EQ) { /* Consume the `='. */ cp_lexer_consume_token (parser->lexer); /* Parse the initializer-clause. */ init = cp_parser_initializer_clause (parser, non_constant_p); } else if (token->type == CPP_OPEN_PAREN) init = cp_parser_parenthesized_expression_list (parser, false, /*cast_p=*/false, /*allow_expansion_p=*/true, non_constant_p); else { /* Anything else is an error. */ cp_parser_error (parser, "expected initializer"); init = error_mark_node; } return init; } /* Parse an initializer-clause. initializer-clause: assignment-expression { initializer-list , [opt] } { } Returns an expression representing the initializer. If the `assignment-expression' production is used the value returned is simply a representation for the expression. Otherwise, a CONSTRUCTOR is returned. The CONSTRUCTOR_ELTS will be the elements of the initializer-list (or NULL, if the last production is used). The TREE_TYPE for the CONSTRUCTOR will be NULL_TREE. There is no way to detect whether or not the optional trailing `,' was provided. NON_CONSTANT_P is as for cp_parser_initializer. */ static tree cp_parser_initializer_clause (cp_parser* parser, bool* non_constant_p) { tree initializer; /* Assume the expression is constant. */ *non_constant_p = false; /* If it is not a `{', then we are looking at an assignment-expression. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_OPEN_BRACE)) { initializer = cp_parser_constant_expression (parser, /*allow_non_constant_p=*/true, non_constant_p); if (!*non_constant_p) initializer = fold_non_dependent_expr (initializer); } else { /* Consume the `{' token. */ cp_lexer_consume_token (parser->lexer); /* Create a CONSTRUCTOR to represent the braced-initializer. */ initializer = make_node (CONSTRUCTOR); /* If it's not a `}', then there is a non-trivial initializer. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_CLOSE_BRACE)) { /* Parse the initializer list. */ CONSTRUCTOR_ELTS (initializer) = cp_parser_initializer_list (parser, non_constant_p); /* A trailing `,' token is allowed. */ if (cp_lexer_next_token_is (parser->lexer, CPP_COMMA)) cp_lexer_consume_token (parser->lexer); } /* Now, there should be a trailing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); } return initializer; } /* Parse an initializer-list. initializer-list: initializer-clause ... [opt] initializer-list , initializer-clause ... [opt] GNU Extension: initializer-list: identifier : initializer-clause initializer-list, identifier : initializer-clause Returns a VEC of constructor_elt. The VALUE of each elt is an expression for the initializer. If the INDEX of the elt is non-NULL, it is the IDENTIFIER_NODE naming the field to initialize. NON_CONSTANT_P is as for cp_parser_initializer. */ static VEC(constructor_elt,gc) * cp_parser_initializer_list (cp_parser* parser, bool* non_constant_p) { VEC(constructor_elt,gc) *v = NULL; /* Assume all of the expressions are constant. */ *non_constant_p = false; /* Parse the rest of the list. */ while (true) { cp_token *token; tree identifier; tree initializer; bool clause_non_constant_p; /* If the next token is an identifier and the following one is a colon, we are looking at the GNU designated-initializer syntax. */ if (cp_parser_allow_gnu_extensions_p (parser) && cp_lexer_next_token_is (parser->lexer, CPP_NAME) && cp_lexer_peek_nth_token (parser->lexer, 2)->type == CPP_COLON) { /* Warn the user that they are using an extension. */ if (pedantic) pedwarn ("ISO C++ does not allow designated initializers"); /* Consume the identifier. */ identifier = cp_lexer_consume_token (parser->lexer)->u.value; /* Consume the `:'. */ cp_lexer_consume_token (parser->lexer); } else identifier = NULL_TREE; /* Parse the initializer. */ initializer = cp_parser_initializer_clause (parser, &clause_non_constant_p); /* If any clause is non-constant, so is the entire initializer. */ if (clause_non_constant_p) *non_constant_p = true; /* If we have an ellipsis, this is an initializer pack expansion. */ if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS)) { /* Consume the `...'. */ cp_lexer_consume_token (parser->lexer); /* Turn the initializer into an initializer expansion. */ initializer = make_pack_expansion (initializer); } /* Add it to the vector. */ CONSTRUCTOR_APPEND_ELT(v, identifier, initializer); /* If the next token is not a comma, we have reached the end of the list. */ if (cp_lexer_next_token_is_not (parser->lexer, CPP_COMMA)) break; /* Peek at the next token. */ token = cp_lexer_peek_nth_token (parser->lexer, 2); /* If the next token is a `}', then we're still done. An initializer-clause can have a trailing `,' after the initializer-list and before the closing `}'. */ if (token->type == CPP_CLOSE_BRACE) break; /* Consume the `,' token. */ cp_lexer_consume_token (parser->lexer); } return v; } /* Classes [gram.class] */ /* Parse a class-name. class-name: identifier template-id TYPENAME_KEYWORD_P is true iff the `typename' keyword has been used to indicate that names looked up in dependent types should be assumed to be types. TEMPLATE_KEYWORD_P is true iff the `template' keyword has been used to indicate that the name that appears next is a template. TAG_TYPE indicates the explicit tag given before the type name, if any. If CHECK_DEPENDENCY_P is FALSE, names are looked up in dependent scopes. If CLASS_HEAD_P is TRUE, this class is the class being defined in a class-head. Returns the TYPE_DECL representing the class. */ static tree cp_parser_class_name (cp_parser *parser, bool typename_keyword_p, bool template_keyword_p, enum tag_types tag_type, bool check_dependency_p, bool class_head_p, bool is_declaration) { tree decl; tree scope; bool typename_p; cp_token *token; /* All class-names start with an identifier. */ token = cp_lexer_peek_token (parser->lexer); if (token->type != CPP_NAME && token->type != CPP_TEMPLATE_ID) { cp_parser_error (parser, "expected class-name"); return error_mark_node; } /* PARSER->SCOPE can be cleared when parsing the template-arguments to a template-id, so we save it here. */ scope = parser->scope; if (scope == error_mark_node) return error_mark_node; /* Any name names a type if we're following the `typename' keyword in a qualified name where the enclosing scope is type-dependent. */ typename_p = (typename_keyword_p && scope && TYPE_P (scope) && dependent_type_p (scope)); /* Handle the common case (an identifier, but not a template-id) efficiently. */ if (token->type == CPP_NAME && !cp_parser_nth_token_starts_template_argument_list_p (parser, 2)) { cp_token *identifier_token; tree identifier; bool ambiguous_p; /* Look for the identifier. */ identifier_token = cp_lexer_peek_token (parser->lexer); ambiguous_p = identifier_token->ambiguous_p; identifier = cp_parser_identifier (parser); /* If the next token isn't an identifier, we are certainly not looking at a class-name. */ if (identifier == error_mark_node) decl = error_mark_node; /* If we know this is a type-name, there's no need to look it up. */ else if (typename_p) decl = identifier; else { tree ambiguous_decls; /* If we already know that this lookup is ambiguous, then we've already issued an error message; there's no reason to check again. */ if (ambiguous_p) { cp_parser_simulate_error (parser); return error_mark_node; } /* If the next token is a `::', then the name must be a type name. [basic.lookup.qual] During the lookup for a name preceding the :: scope resolution operator, object, function, and enumerator names are ignored. */ if (cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) tag_type = typename_type; /* Look up the name. */ decl = cp_parser_lookup_name (parser, identifier, tag_type, /*is_template=*/false, /*is_namespace=*/false, check_dependency_p, &ambiguous_decls); if (ambiguous_decls) { error ("reference to %qD is ambiguous", identifier); print_candidates (ambiguous_decls); if (cp_parser_parsing_tentatively (parser)) { identifier_token->ambiguous_p = true; cp_parser_simulate_error (parser); } return error_mark_node; } } } else { /* Try a template-id. */ decl = cp_parser_template_id (parser, template_keyword_p, check_dependency_p, is_declaration); if (decl == error_mark_node) return error_mark_node; } decl = cp_parser_maybe_treat_template_as_class (decl, class_head_p); /* If this is a typename, create a TYPENAME_TYPE. */ if (typename_p && decl != error_mark_node) { decl = make_typename_type (scope, decl, typename_type, /*complain=*/tf_error); if (decl != error_mark_node) decl = TYPE_NAME (decl); } /* Check to see that it is really the name of a class. */ if (TREE_CODE (decl) == TEMPLATE_ID_EXPR && TREE_CODE (TREE_OPERAND (decl, 0)) == IDENTIFIER_NODE && cp_lexer_next_token_is (parser->lexer, CPP_SCOPE)) /* Situations like this: template struct A { typename T::template X::I i; }; are problematic. Is `T::template X' a class-name? The standard does not seem to be definitive, but there is no other valid interpretation of the following `::'. Therefore, those names are considered class-names. */ { decl = make_typename_type (scope, decl, tag_type, tf_error); if (decl != error_mark_node) decl = TYPE_NAME (decl); } else if (TREE_CODE (decl) != TYPE_DECL || TREE_TYPE (decl) == error_mark_node || !MAYBE_CLASS_TYPE_P (TREE_TYPE (decl))) decl = error_mark_node; if (decl == error_mark_node) cp_parser_error (parser, "expected class-name"); return decl; } /* Parse a class-specifier. class-specifier: class-head { member-specification [opt] } Returns the TREE_TYPE representing the class. */ static tree cp_parser_class_specifier (cp_parser* parser) { cp_token *token; tree type; tree attributes = NULL_TREE; int has_trailing_semicolon; bool nested_name_specifier_p; unsigned saved_num_template_parameter_lists; bool saved_in_function_body; tree old_scope = NULL_TREE; tree scope = NULL_TREE; tree bases; push_deferring_access_checks (dk_no_deferred); /* Parse the class-head. */ type = cp_parser_class_head (parser, &nested_name_specifier_p, &attributes, &bases); /* If the class-head was a semantic disaster, skip the entire body of the class. */ if (!type) { cp_parser_skip_to_end_of_block_or_statement (parser); pop_deferring_access_checks (); return error_mark_node; } /* Look for the `{'. */ if (!cp_parser_require (parser, CPP_OPEN_BRACE, "`{'")) { pop_deferring_access_checks (); return error_mark_node; } /* Process the base classes. If they're invalid, skip the entire class body. */ if (!xref_basetypes (type, bases)) { /* Consuming the closing brace yields better error messages later on. */ if (cp_parser_skip_to_closing_brace (parser)) cp_lexer_consume_token (parser->lexer); pop_deferring_access_checks (); return error_mark_node; } /* Issue an error message if type-definitions are forbidden here. */ cp_parser_check_type_definition (parser); /* Remember that we are defining one more class. */ ++parser->num_classes_being_defined; /* Inside the class, surrounding template-parameter-lists do not apply. */ saved_num_template_parameter_lists = parser->num_template_parameter_lists; parser->num_template_parameter_lists = 0; /* We are not in a function body. */ saved_in_function_body = parser->in_function_body; parser->in_function_body = false; /* Start the class. */ if (nested_name_specifier_p) { scope = CP_DECL_CONTEXT (TYPE_MAIN_DECL (type)); old_scope = push_inner_scope (scope); } type = begin_class_definition (type, attributes); if (type == error_mark_node) /* If the type is erroneous, skip the entire body of the class. */ cp_parser_skip_to_closing_brace (parser); else /* Parse the member-specification. */ cp_parser_member_specification_opt (parser); /* Look for the trailing `}'. */ cp_parser_require (parser, CPP_CLOSE_BRACE, "`}'"); /* We get better error messages by noticing a common problem: a missing trailing `;'. */ token = cp_lexer_peek_token (parser->lexer); has_trailing_semicolon = (token->type == CPP_SEMICOLON); /* Look for trailing attributes to apply to this class. */ if (cp_parser_allow_gnu_extensions_p (parser)) attributes = cp_parser_attributes_opt (parser); if (type != error_mark_node) type = finish_struct (type, attributes); if (nested_name_specifier_p) pop_inner_scope (old_scope, scope); /* If this class is not itself within the scope of another class, then we need to parse the bodies of all of the queued function definitions. Note that the queued functions defined in a class are not always processed immediately following the class-specifier for that class. Consider: struct A { struct B { void f() { sizeof (A); } }; }; If `f' were processed before the processing of `A' were completed, there would be no way to compute the size of `A'. Note that the nesting we are interested in here is lexical -- not the semantic nesting given by TYPE_CONTEXT. In particular, for: struct A { struct B; }; struct A::B { void f() { } }; there is no need to delay the parsing of `A::B::f'. */ if (--parser->num_classes_being_defined == 0) { tree queue_entry; tree fn; tree class_type = NULL_TREE; tree pushed_scope = NULL_TREE; /* In a first pass, parse default arguments to the functions. Then, in a second pass, parse the bodies of the functions. This two-phased approach handles cases like: struct S { void f() { g(); } void g(int i = 3); }; */ for (TREE_PURPOSE (parser->unparsed_functions_queues) = nreverse (TREE_PURPOSE (parser->unparsed_functions_queues)); (queue_entry = TREE_PURPOSE (parser->unparsed_functions_queues)); TREE_PURPOSE (parser->unparsed_functions_queues) = TREE_CHAIN (TREE_PURPOSE (parser->unparsed_functions_queues))) { fn = TREE_VALUE (queue_entry); /* If there are default arguments that have not yet been processed, take care of them now. */ if (class_type != TREE_PURPOSE (queue_entry)) { if (pushed_scope) pop_scope (pushed_scope); class_type = TREE_PURPOSE (queue_entry); pushed_scope = push_scope (class_type); } /* Make sure that any template parameters are in scope. */ maybe_begin_member_template_processing (fn); /* Parse the default argument expressions. */ cp_parser_late_parsing_default_args (parser, fn); /* Remove any template parameters from the symbol table. */ maybe_end_member_template_processing (); } if (pushed_scope) pop_scope (pushed_scope); /* Now parse the body of the functions. */ for (TREE_VALUE (parser->unparsed_functions_queues) = nreverse (TREE_VALUE (parser->unparsed_functions_queues)); (queue_entry = TREE_VALUE (parser->unparsed_functions_queues)); TREE_VALUE (parser->unparsed_functions_queues) = TREE_CHAIN (TREE_VALUE (parser->unparsed_functions_queues))) { /* Figure out which function we need to process. */ fn = TREE_VALUE (queue_entry); /* Parse the function. */ cp_parser_late_parsing_for_member (parser, fn); } } /* Put back any saved access checks. */ pop_deferring_access_checks (); /* Restore saved state. */ parser->in_function_body = saved_in_function_body; parser->num_template_parameter_lists = saved_num_template_parameter_lists; return type; } /* Parse a class-head. class-head: class-key identifier [opt] base-clause [opt] class-key nested-name-specifier identifier base-clause [opt] class-key nested-name-specifier [opt] template-id base-clause [opt] GNU Extensions: class-key attributes identifier [opt] base-clause [opt] class-key attributes nested-name-specifier identifier base-clause [opt] class-key attributes nested-name-specifier [opt] template-id base-clause [opt] Upon return BASES is initialized to the list of base classes (or NULL, if there are none) in the same form returned by cp_parser_base_clause. Returns the TYPE of the indicated class. Sets *NESTED_NAME_SPECIFIER_P to TRUE iff one of the productions involving a nested-name-specifier was used, and FALSE otherwise. Returns error_mark_node if this is not a class-head. Returns NULL_TREE if the class-head is syntactically valid, but semantically invalid in a way that means we should skip the entire body of the class. */ static tree cp_parser_class_head (cp_parser* parser, bool* nested_name_specifier_p, tree *attributes_p, tree *bases) { tree nested_name_specifier; enum tag_types class_key; tree id = NULL_TREE; tree type = NULL_TREE; tree attributes; bool template_id_p = false; bool qualified_p = false; bool invalid_nested_name_p = false; bool invalid_explicit_specialization_p = false; tree pushed_scope = NULL_TREE; unsigned num_templates; /* Assume no nested-name-specifier will be present. */ *nested_name_specifier_p = false; /* Assume no template parameter lists will be used in defining the type. */ num_templates = 0; *bases = NULL_TREE; /* Look for the class-key. */ class_key = cp_parser_class_key (parser); if (class_key == none_type) return error_mark_node; /* Parse the attributes. */ attributes = cp_parser_attributes_opt (parser); /* If the next token is `::', that is invalid -- but sometimes people do try to write: struct ::S {}; Handle this gracefully by accepting the extra qualifier, and then issuing an error about it later if this really is a class-head. If it turns out just to be an elaborated type specifier, remain silent. */ if (cp_parser_global_scope_opt (parser, /*current_scope_valid_p=*/false)) qualified_p = true; push_deferring_access_checks (dk_no_check); /* Determine the name of the class. Begin by looking for an optional nested-name-specifier. */ nested_name_specifier = cp_parser_nested_name_specifier_opt (parser, /*typename_keyword_p=*/false, /*check_dependency_p=*/false, /*type_p=*/false, /*is_declaration=*/false); /* If there was a nested-name-specifier, then there *must* be an identifier. */ if (nested_name_specifier) { /* Although the grammar says `identifier', it really means `class-name' or `template-name'. You are only allowed to define a class that has already been declared with this syntax. The proposed resolution for Core Issue 180 says that wherever you see `class T::X' you should treat `X' as a type-name. It is OK to define an inaccessible class; for example: class A { class B; }; class A::B {}; We do not know if we will see a class-name, or a template-name. We look for a class-name first, in case the class-name is a template-id; if we looked for the template-name first we would stop after the template-name. */ cp_parser_parse_tentatively (parser); type = cp_parser_class_name (parser, /*typename_keyword_p=*/false, /*template_keyword_p=*/false, class_type, /*check_dependency_p=*/false, /*class_head_p=*/true, /*is_declaration=*/false); /* If that didn't work, ignore the nested-name-specifier. */ if (!cp_parser_parse_definitely (parser)) { invalid_nested_name_p = true; id = cp_parser_identifier (parser); if (id == error_mark_node) id = NULL_TREE; } /* If we could not find a corresponding TYPE, treat this declaration like an unqualified declaration. */ if (type == error_mark_node) nested_name_specifier = NULL_TREE; /* Otherwise, count the number of templates used in TYPE and its containing scopes. */ else { tree scope; for (scope = TREE_TYPE (type); scope && TREE_CODE (scope) != NAMESPACE_DECL; scope = (TYPE_P (scope) ? TYPE_CONTEXT (scope) : DECL_CONTEXT (scope))) if (TYPE_P (scope) && CLASS_TYPE_P (scope) && CLASSTYPE_TEMPLATE_INFO (scope) && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (scope)) && !CLASSTYPE_TEMPLATE_SPECIALIZATION (scope)) ++num_templates; } } /* Otherwise, the identifier is optional. */ else { /* We don't know whether what comes next is a template-id, an identifier, or nothing at all. */ cp_parser_parse_tentatively (parser); /* Check for a template-id. */ id = cp_parser_template_id (parser, /*template_keyword_p=*/false, /*check_dependency_p=*/true, /*is_declaration=*/true); /* If that didn't work, it could still be an identifier. */ if (!cp_parser_parse_definitely (parser)) { if (cp_lexer_next_token_is (parser->lexer, CPP_NAME)) id = cp_parser_identifier (parser); else id = NULL_TREE; } else { template_id_p = true; ++num_templates; } } pop_deferring_access_checks (); if (id) cp_parser_check_for_invalid_template_id (parser, id); /* If it's not a `:' or a `{' then we can't really be looking at a class-head, since a class-head only appears as part of a class-specifier. We have to detect this situation before calling xref_tag, since that has irreversible side-effects. */ if (!cp_parser_next_token_starts_class_definition_p (parser)) { cp_parser_error (parser, "expected %<{%> or %<:%>"); return error_mark_node; } /* At this point, we're going ahead with the class-specifier, even if some other problem occurs. */ cp_parser_commit_to_tentative_parse (parser); /* Issue the error about the overly-qualified name now. */ if (qualified_p) cp_parser_error (parser, "global qualification of class name is invalid"); else if (invalid_nested_name_p) cp_parser_error (parser, "qualified name does not name a class"); else if (nested_name_specifier) { tree scope; /* Reject typedef-names in class heads. */ if (!DECL_IMPLICIT_TYPEDEF_P (type)) { error ("invalid class name in declaration of %qD", type); type = NULL_TREE; goto done; } /* Figure out in what scope the declaration is being placed. */ scope = current_scope (); /* If that scope does not contain the scope in which the class was originally declared, the program is invalid. */ if (scope && !is_ancestor (scope, nested_name_specifier)) { if (at_namespace_scope_p ()) error ("declaration of %qD in namespace %qD which does not " "enclose %qD", type, scope, nested_name_specifier); else error ("declaration of %qD in %qD which does not enclose %qD", type, scope, nested_name_specifier); type = NULL_TREE; goto done; } /* [dcl.meaning] A declarator-id shall not be qualified exception of the definition of a ... nested class outside of its class ... [or] a the definition or explicit instantiation of a class member of a namespace outside of its namespace. */ if (scope == nested_name_specifier) { pedwarn ("extra qualification ignored"); nested_name_specifier = NULL_TREE; num_templates = 0; } } /* An explicit-specialization must be preceded by "template <>". If it is not, try to recover gracefully. */ if (at_namespace_scope_p () && parser->num_template_parameter_lists == 0 && template_id_p) { error ("an explicit specialization must be preceded by %