/* Definitions for C++ name lookup routines. Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. Contributed by Gabriel Dos Reis 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 "flags.h" #include "tree.h" #include "cp-tree.h" #include "name-lookup.h" #include "timevar.h" #include "toplev.h" #include "diagnostic.h" #include "debug.h" #include "c-pragma.h" /* The bindings for a particular name in a particular scope. */ struct scope_binding { tree value; tree type; }; #define EMPTY_SCOPE_BINDING { NULL_TREE, NULL_TREE } static cxx_scope *innermost_nonclass_level (void); static cxx_binding *binding_for_name (cxx_scope *, tree); static tree lookup_name_innermost_nonclass_level (tree); static tree push_overloaded_decl (tree, int, bool); static bool lookup_using_namespace (tree, struct scope_binding *, tree, tree, int); static bool qualified_lookup_using_namespace (tree, tree, struct scope_binding *, int); static tree lookup_type_current_level (tree); static tree push_using_directive (tree); /* The :: namespace. */ tree global_namespace; /* The name of the anonymous namespace, throughout this translation unit. */ static GTY(()) tree anonymous_namespace_name; /* Initialize anonymous_namespace_name if necessary, and return it. */ static tree get_anonymous_namespace_name(void) { if (!anonymous_namespace_name) { /* The anonymous namespace has to have a unique name if typeinfo objects are being compared by name. */ if (! flag_weak || ! SUPPORTS_ONE_ONLY) anonymous_namespace_name = get_file_function_name ("N"); else /* The demangler expects anonymous namespaces to be called something starting with '_GLOBAL__N_'. */ anonymous_namespace_name = get_identifier ("_GLOBAL__N_1"); } return anonymous_namespace_name; } /* Compute the chain index of a binding_entry given the HASH value of its name and the total COUNT of chains. COUNT is assumed to be a power of 2. */ #define ENTRY_INDEX(HASH, COUNT) (((HASH) >> 3) & ((COUNT) - 1)) /* A free list of "binding_entry"s awaiting for re-use. */ static GTY((deletable)) binding_entry free_binding_entry = NULL; /* Create a binding_entry object for (NAME, TYPE). */ static inline binding_entry binding_entry_make (tree name, tree type) { binding_entry entry; if (free_binding_entry) { entry = free_binding_entry; free_binding_entry = entry->chain; } else entry = GGC_NEW (struct binding_entry_s); entry->name = name; entry->type = type; entry->chain = NULL; return entry; } /* Put ENTRY back on the free list. */ #if 0 static inline void binding_entry_free (binding_entry entry) { entry->name = NULL; entry->type = NULL; entry->chain = free_binding_entry; free_binding_entry = entry; } #endif /* The datatype used to implement the mapping from names to types at a given scope. */ struct binding_table_s GTY(()) { /* Array of chains of "binding_entry"s */ binding_entry * GTY((length ("%h.chain_count"))) chain; /* The number of chains in this table. This is the length of the the member "chain" considered as an array. */ size_t chain_count; /* Number of "binding_entry"s in this table. */ size_t entry_count; }; /* Construct TABLE with an initial CHAIN_COUNT. */ static inline void binding_table_construct (binding_table table, size_t chain_count) { table->chain_count = chain_count; table->entry_count = 0; table->chain = GGC_CNEWVEC (binding_entry, table->chain_count); } /* Make TABLE's entries ready for reuse. */ #if 0 static void binding_table_free (binding_table table) { size_t i; size_t count; if (table == NULL) return; for (i = 0, count = table->chain_count; i < count; ++i) { binding_entry temp = table->chain[i]; while (temp != NULL) { binding_entry entry = temp; temp = entry->chain; binding_entry_free (entry); } table->chain[i] = NULL; } table->entry_count = 0; } #endif /* Allocate a table with CHAIN_COUNT, assumed to be a power of two. */ static inline binding_table binding_table_new (size_t chain_count) { binding_table table = GGC_NEW (struct binding_table_s); table->chain = NULL; binding_table_construct (table, chain_count); return table; } /* Expand TABLE to twice its current chain_count. */ static void binding_table_expand (binding_table table) { const size_t old_chain_count = table->chain_count; const size_t old_entry_count = table->entry_count; const size_t new_chain_count = 2 * old_chain_count; binding_entry *old_chains = table->chain; size_t i; binding_table_construct (table, new_chain_count); for (i = 0; i < old_chain_count; ++i) { binding_entry entry = old_chains[i]; for (; entry != NULL; entry = old_chains[i]) { const unsigned int hash = IDENTIFIER_HASH_VALUE (entry->name); const size_t j = ENTRY_INDEX (hash, new_chain_count); old_chains[i] = entry->chain; entry->chain = table->chain[j]; table->chain[j] = entry; } } table->entry_count = old_entry_count; } /* Insert a binding for NAME to TYPE into TABLE. */ static void binding_table_insert (binding_table table, tree name, tree type) { const unsigned int hash = IDENTIFIER_HASH_VALUE (name); const size_t i = ENTRY_INDEX (hash, table->chain_count); binding_entry entry = binding_entry_make (name, type); entry->chain = table->chain[i]; table->chain[i] = entry; ++table->entry_count; if (3 * table->chain_count < 5 * table->entry_count) binding_table_expand (table); } /* Return the binding_entry, if any, that maps NAME. */ binding_entry binding_table_find (binding_table table, tree name) { const unsigned int hash = IDENTIFIER_HASH_VALUE (name); binding_entry entry = table->chain[ENTRY_INDEX (hash, table->chain_count)]; while (entry != NULL && entry->name != name) entry = entry->chain; return entry; } /* Apply PROC -- with DATA -- to all entries in TABLE. */ void binding_table_foreach (binding_table table, bt_foreach_proc proc, void *data) { const size_t chain_count = table->chain_count; size_t i; for (i = 0; i < chain_count; ++i) { binding_entry entry = table->chain[i]; for (; entry != NULL; entry = entry->chain) proc (entry, data); } } #ifndef ENABLE_SCOPE_CHECKING # define ENABLE_SCOPE_CHECKING 0 #else # define ENABLE_SCOPE_CHECKING 1 #endif /* A free list of "cxx_binding"s, connected by their PREVIOUS. */ static GTY((deletable)) cxx_binding *free_bindings; /* Initialize VALUE and TYPE field for BINDING, and set the PREVIOUS field to NULL. */ static inline void cxx_binding_init (cxx_binding *binding, tree value, tree type) { binding->value = value; binding->type = type; binding->previous = NULL; } /* (GC)-allocate a binding object with VALUE and TYPE member initialized. */ static cxx_binding * cxx_binding_make (tree value, tree type) { cxx_binding *binding; if (free_bindings) { binding = free_bindings; free_bindings = binding->previous; } else binding = GGC_NEW (cxx_binding); cxx_binding_init (binding, value, type); return binding; } /* Put BINDING back on the free list. */ static inline void cxx_binding_free (cxx_binding *binding) { binding->scope = NULL; binding->previous = free_bindings; free_bindings = binding; } /* Create a new binding for NAME (with the indicated VALUE and TYPE bindings) in the class scope indicated by SCOPE. */ static cxx_binding * new_class_binding (tree name, tree value, tree type, cxx_scope *scope) { cp_class_binding *cb; cxx_binding *binding; if (VEC_length (cp_class_binding, scope->class_shadowed)) { cp_class_binding *old_base; old_base = VEC_index (cp_class_binding, scope->class_shadowed, 0); if (VEC_reserve (cp_class_binding, gc, scope->class_shadowed, 1)) { /* Fixup the current bindings, as they might have moved. */ size_t i; for (i = 0; VEC_iterate (cp_class_binding, scope->class_shadowed, i, cb); i++) { cxx_binding **b; b = &IDENTIFIER_BINDING (cb->identifier); while (*b != &old_base[i].base) b = &((*b)->previous); *b = &cb->base; } } cb = VEC_quick_push (cp_class_binding, scope->class_shadowed, NULL); } else cb = VEC_safe_push (cp_class_binding, gc, scope->class_shadowed, NULL); cb->identifier = name; binding = &cb->base; binding->scope = scope; cxx_binding_init (binding, value, type); return binding; } /* Make DECL the innermost binding for ID. The LEVEL is the binding level at which this declaration is being bound. */ static void push_binding (tree id, tree decl, cxx_scope* level) { cxx_binding *binding; if (level != class_binding_level) { binding = cxx_binding_make (decl, NULL_TREE); binding->scope = level; } else binding = new_class_binding (id, decl, /*type=*/NULL_TREE, level); /* Now, fill in the binding information. */ binding->previous = IDENTIFIER_BINDING (id); INHERITED_VALUE_BINDING_P (binding) = 0; LOCAL_BINDING_P (binding) = (level != class_binding_level); /* And put it on the front of the list of bindings for ID. */ IDENTIFIER_BINDING (id) = binding; } /* Remove the binding for DECL which should be the innermost binding for ID. */ void pop_binding (tree id, tree decl) { cxx_binding *binding; if (id == NULL_TREE) /* It's easiest to write the loops that call this function without checking whether or not the entities involved have names. We get here for such an entity. */ return; /* Get the innermost binding for ID. */ binding = IDENTIFIER_BINDING (id); /* The name should be bound. */ gcc_assert (binding != NULL); /* The DECL will be either the ordinary binding or the type binding for this identifier. Remove that binding. */ if (binding->value == decl) binding->value = NULL_TREE; else { gcc_assert (binding->type == decl); binding->type = NULL_TREE; } if (!binding->value && !binding->type) { /* We're completely done with the innermost binding for this identifier. Unhook it from the list of bindings. */ IDENTIFIER_BINDING (id) = binding->previous; /* Add it to the free list. */ cxx_binding_free (binding); } } /* BINDING records an existing declaration for a name in the current scope. But, DECL is another declaration for that same identifier in the same scope. This is the `struct stat' hack whereby a non-typedef class name or enum-name can be bound at the same level as some other kind of entity. 3.3.7/1 A class name (9.1) or enumeration name (7.2) can be hidden by the name of an object, function, or enumerator declared in the same scope. If a class or enumeration name and an object, function, or enumerator are declared in the same scope (in any order) with the same name, the class or enumeration name is hidden wherever the object, function, or enumerator name is visible. It's the responsibility of the caller to check that inserting this name is valid here. Returns nonzero if the new binding was successful. */ static bool supplement_binding (cxx_binding *binding, tree decl) { tree bval = binding->value; bool ok = true; timevar_push (TV_NAME_LOOKUP); if (TREE_CODE (decl) == TYPE_DECL && DECL_ARTIFICIAL (decl)) /* The new name is the type name. */ binding->type = decl; else if (/* BVAL is null when push_class_level_binding moves an inherited type-binding out of the way to make room for a new value binding. */ !bval /* BVAL is error_mark_node when DECL's name has been used in a non-class scope prior declaration. In that case, we should have already issued a diagnostic; for graceful error recovery purpose, pretend this was the intended declaration for that name. */ || bval == error_mark_node /* If BVAL is anticipated but has not yet been declared, pretend it is not there at all. */ || (TREE_CODE (bval) == FUNCTION_DECL && DECL_ANTICIPATED (bval) && !DECL_HIDDEN_FRIEND_P (bval))) binding->value = decl; else if (TREE_CODE (bval) == TYPE_DECL && DECL_ARTIFICIAL (bval)) { /* The old binding was a type name. It was placed in VALUE field because it was thought, at the point it was declared, to be the only entity with such a name. Move the type name into the type slot; it is now hidden by the new binding. */ binding->type = bval; binding->value = decl; binding->value_is_inherited = false; } else if (TREE_CODE (bval) == TYPE_DECL && TREE_CODE (decl) == TYPE_DECL && DECL_NAME (decl) == DECL_NAME (bval) && binding->scope->kind != sk_class && (same_type_p (TREE_TYPE (decl), TREE_TYPE (bval)) /* If either type involves template parameters, we must wait until instantiation. */ || uses_template_parms (TREE_TYPE (decl)) || uses_template_parms (TREE_TYPE (bval)))) /* We have two typedef-names, both naming the same type to have the same name. In general, this is OK because of: [dcl.typedef] In a given scope, a typedef specifier can be used to redefine the name of any type declared in that scope to refer to the type to which it already refers. However, in class scopes, this rule does not apply due to the stricter language in [class.mem] prohibiting redeclarations of members. */ ok = false; /* There can be two block-scope declarations of the same variable, so long as they are `extern' declarations. However, there cannot be two declarations of the same static data member: [class.mem] A member shall not be declared twice in the member-specification. */ else if (TREE_CODE (decl) == VAR_DECL && TREE_CODE (bval) == VAR_DECL && DECL_EXTERNAL (decl) && DECL_EXTERNAL (bval) && !DECL_CLASS_SCOPE_P (decl)) { duplicate_decls (decl, binding->value, /*newdecl_is_friend=*/false); ok = false; } else if (TREE_CODE (decl) == NAMESPACE_DECL && TREE_CODE (bval) == NAMESPACE_DECL && DECL_NAMESPACE_ALIAS (decl) && DECL_NAMESPACE_ALIAS (bval) && ORIGINAL_NAMESPACE (bval) == ORIGINAL_NAMESPACE (decl)) /* [namespace.alias] In a declarative region, a namespace-alias-definition can be used to redefine a namespace-alias declared in that declarative region to refer only to the namespace to which it already refers. */ ok = false; else { error ("declaration of %q#D", decl); error ("conflicts with previous declaration %q+#D", bval); ok = false; } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, ok); } /* Add DECL to the list of things declared in B. */ static void add_decl_to_level (tree decl, cxx_scope *b) { /* We used to record virtual tables as if they were ordinary variables, but no longer do so. */ gcc_assert (!(TREE_CODE (decl) == VAR_DECL && DECL_VIRTUAL_P (decl))); if (TREE_CODE (decl) == NAMESPACE_DECL && !DECL_NAMESPACE_ALIAS (decl)) { TREE_CHAIN (decl) = b->namespaces; b->namespaces = decl; } else { /* We build up the list in reverse order, and reverse it later if necessary. */ TREE_CHAIN (decl) = b->names; b->names = decl; b->names_size++; /* If appropriate, add decl to separate list of statics. We include extern variables because they might turn out to be static later. It's OK for this list to contain a few false positives. */ if (b->kind == sk_namespace) if ((TREE_CODE (decl) == VAR_DECL && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))) || (TREE_CODE (decl) == FUNCTION_DECL && (!TREE_PUBLIC (decl) || DECL_DECLARED_INLINE_P (decl)))) VEC_safe_push (tree, gc, b->static_decls, decl); } } /* Record a decl-node X as belonging to the current lexical scope. Check for errors (such as an incompatible declaration for the same name already seen in the same scope). IS_FRIEND is true if X is declared as a friend. Returns either X or an old decl for the same name. If an old decl is returned, it may have been smashed to agree with what X says. */ tree pushdecl_maybe_friend (tree x, bool is_friend) { tree t; tree name; int need_new_binding; timevar_push (TV_NAME_LOOKUP); if (x == error_mark_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node); need_new_binding = 1; if (DECL_TEMPLATE_PARM_P (x)) /* Template parameters have no context; they are not X::T even when declared within a class or namespace. */ ; else { if (current_function_decl && x != current_function_decl /* A local declaration for a function doesn't constitute nesting. */ && TREE_CODE (x) != FUNCTION_DECL /* A local declaration for an `extern' variable is in the scope of the current namespace, not the current function. */ && !(TREE_CODE (x) == VAR_DECL && DECL_EXTERNAL (x)) && !DECL_CONTEXT (x)) DECL_CONTEXT (x) = current_function_decl; /* If this is the declaration for a namespace-scope function, but the declaration itself is in a local scope, mark the declaration. */ if (TREE_CODE (x) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (x) && current_function_decl && x != current_function_decl) DECL_LOCAL_FUNCTION_P (x) = 1; } name = DECL_NAME (x); if (name) { int different_binding_level = 0; if (TREE_CODE (name) == TEMPLATE_ID_EXPR) name = TREE_OPERAND (name, 0); /* In case this decl was explicitly namespace-qualified, look it up in its namespace context. */ if (DECL_NAMESPACE_SCOPE_P (x) && namespace_bindings_p ()) t = namespace_binding (name, DECL_CONTEXT (x)); else t = lookup_name_innermost_nonclass_level (name); /* [basic.link] If there is a visible declaration of an entity with linkage having the same name and type, ignoring entities declared outside the innermost enclosing namespace scope, the block scope declaration declares that same entity and receives the linkage of the previous declaration. */ if (! t && current_function_decl && x != current_function_decl && (TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL) && DECL_EXTERNAL (x)) { /* Look in block scope. */ t = innermost_non_namespace_value (name); /* Or in the innermost namespace. */ if (! t) t = namespace_binding (name, DECL_CONTEXT (x)); /* Does it have linkage? Note that if this isn't a DECL, it's an OVERLOAD, which is OK. */ if (t && DECL_P (t) && ! (TREE_STATIC (t) || DECL_EXTERNAL (t))) t = NULL_TREE; if (t) different_binding_level = 1; } /* If we are declaring a function, and the result of name-lookup was an OVERLOAD, look for an overloaded instance that is actually the same as the function we are declaring. (If there is one, we have to merge our declaration with the previous declaration.) */ if (t && TREE_CODE (t) == OVERLOAD) { tree match; if (TREE_CODE (x) == FUNCTION_DECL) for (match = t; match; match = OVL_NEXT (match)) { if (decls_match (OVL_CURRENT (match), x)) break; } else /* Just choose one. */ match = t; if (match) t = OVL_CURRENT (match); else t = NULL_TREE; } if (t && t != error_mark_node) { if (different_binding_level) { if (decls_match (x, t)) /* The standard only says that the local extern inherits linkage from the previous decl; in particular, default args are not shared. Add the decl into a hash table to make sure only the previous decl in this case is seen by the middle end. */ { struct cxx_int_tree_map *h; void **loc; TREE_PUBLIC (x) = TREE_PUBLIC (t); if (cp_function_chain->extern_decl_map == NULL) cp_function_chain->extern_decl_map = htab_create_ggc (20, cxx_int_tree_map_hash, cxx_int_tree_map_eq, NULL); h = GGC_NEW (struct cxx_int_tree_map); h->uid = DECL_UID (x); h->to = t; loc = htab_find_slot_with_hash (cp_function_chain->extern_decl_map, h, h->uid, INSERT); *(struct cxx_int_tree_map **) loc = h; } } else if (TREE_CODE (t) == PARM_DECL) { gcc_assert (DECL_CONTEXT (t)); /* Check for duplicate params. */ if (duplicate_decls (x, t, is_friend)) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } else if ((DECL_EXTERN_C_FUNCTION_P (x) || DECL_FUNCTION_TEMPLATE_P (x)) && is_overloaded_fn (t)) /* Don't do anything just yet. */; else if (t == wchar_decl_node) { if (pedantic && ! DECL_IN_SYSTEM_HEADER (x)) pedwarn ("redeclaration of % as %qT", TREE_TYPE (x)); /* Throw away the redeclaration. */ POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } else { tree olddecl = duplicate_decls (x, t, is_friend); /* If the redeclaration failed, we can stop at this point. */ if (olddecl == error_mark_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node); if (olddecl) { if (TREE_CODE (t) == TYPE_DECL) SET_IDENTIFIER_TYPE_VALUE (name, TREE_TYPE (t)); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } else if (DECL_MAIN_P (x) && TREE_CODE (t) == FUNCTION_DECL) { /* A redeclaration of main, but not a duplicate of the previous one. [basic.start.main] This function shall not be overloaded. */ error ("invalid redeclaration of %q+D", t); error ("as %qD", x); /* We don't try to push this declaration since that causes a crash. */ POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, x); } } } if (TREE_CODE (x) == FUNCTION_DECL || DECL_FUNCTION_TEMPLATE_P (x)) check_default_args (x); check_template_shadow (x); /* If this is a function conjured up by the back end, massage it so it looks friendly. */ if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_LANG_SPECIFIC (x)) { retrofit_lang_decl (x); SET_DECL_LANGUAGE (x, lang_c); } if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_FUNCTION_MEMBER_P (x)) { t = push_overloaded_decl (x, PUSH_LOCAL, is_friend); if (t != x) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); if (!namespace_bindings_p ()) /* We do not need to create a binding for this name; push_overloaded_decl will have already done so if necessary. */ need_new_binding = 0; } else if (DECL_FUNCTION_TEMPLATE_P (x) && DECL_NAMESPACE_SCOPE_P (x)) { t = push_overloaded_decl (x, PUSH_GLOBAL, is_friend); if (t == x) add_decl_to_level (x, NAMESPACE_LEVEL (CP_DECL_CONTEXT (t))); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } /* If declaring a type as a typedef, copy the type (unless we're at line 0), and install this TYPE_DECL as the new type's typedef name. See the extensive comment in ../c-decl.c (pushdecl). */ if (TREE_CODE (x) == TYPE_DECL) { tree type = TREE_TYPE (x); if (DECL_IS_BUILTIN (x)) { if (TYPE_NAME (type) == 0) TYPE_NAME (type) = x; } else if (type != error_mark_node && TYPE_NAME (type) != x /* We don't want to copy the type when all we're doing is making a TYPE_DECL for the purposes of inlining. */ && (!TYPE_NAME (type) || TYPE_NAME (type) != DECL_ABSTRACT_ORIGIN (x))) { DECL_ORIGINAL_TYPE (x) = type; type = build_variant_type_copy (type); TYPE_STUB_DECL (type) = TYPE_STUB_DECL (DECL_ORIGINAL_TYPE (x)); TYPE_NAME (type) = x; TREE_TYPE (x) = type; } if (type != error_mark_node && TYPE_NAME (type) && TYPE_IDENTIFIER (type)) set_identifier_type_value (DECL_NAME (x), x); } /* Multiple external decls of the same identifier ought to match. We get warnings about inline functions where they are defined. We get warnings about other functions from push_overloaded_decl. Avoid duplicate warnings where they are used. */ if (TREE_PUBLIC (x) && TREE_CODE (x) != FUNCTION_DECL) { tree decl; decl = IDENTIFIER_NAMESPACE_VALUE (name); if (decl && TREE_CODE (decl) == OVERLOAD) decl = OVL_FUNCTION (decl); if (decl && decl != error_mark_node && (DECL_EXTERNAL (decl) || TREE_PUBLIC (decl)) /* If different sort of thing, we already gave an error. */ && TREE_CODE (decl) == TREE_CODE (x) && !same_type_p (TREE_TYPE (x), TREE_TYPE (decl))) { pedwarn ("type mismatch with previous external decl of %q#D", x); pedwarn ("previous external decl of %q+#D", decl); } } if (TREE_CODE (x) == FUNCTION_DECL && is_friend && !flag_friend_injection) { /* This is a new declaration of a friend function, so hide it from ordinary function lookup. */ DECL_ANTICIPATED (x) = 1; DECL_HIDDEN_FRIEND_P (x) = 1; } /* This name is new in its binding level. Install the new declaration and return it. */ if (namespace_bindings_p ()) { /* Install a global value. */ /* If the first global decl has external linkage, warn if we later see static one. */ if (IDENTIFIER_GLOBAL_VALUE (name) == NULL_TREE && TREE_PUBLIC (x)) TREE_PUBLIC (name) = 1; /* Bind the name for the entity. */ if (!(TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x) && t != NULL_TREE) && (TREE_CODE (x) == TYPE_DECL || TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == NAMESPACE_DECL || TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == TEMPLATE_DECL)) SET_IDENTIFIER_NAMESPACE_VALUE (name, x); /* If new decl is `static' and an `extern' was seen previously, warn about it. */ if (x != NULL_TREE && t != NULL_TREE && decls_match (x, t)) warn_extern_redeclared_static (x, t); } else { /* Here to install a non-global value. */ tree oldlocal = innermost_non_namespace_value (name); tree oldglobal = IDENTIFIER_NAMESPACE_VALUE (name); if (need_new_binding) { push_local_binding (name, x, 0); /* Because push_local_binding will hook X on to the current_binding_level's name list, we don't want to do that again below. */ need_new_binding = 0; } /* If this is a TYPE_DECL, push it into the type value slot. */ if (TREE_CODE (x) == TYPE_DECL) set_identifier_type_value (name, x); /* Clear out any TYPE_DECL shadowed by a namespace so that we won't think this is a type. The C struct hack doesn't go through namespaces. */ if (TREE_CODE (x) == NAMESPACE_DECL) set_identifier_type_value (name, NULL_TREE); if (oldlocal) { tree d = oldlocal; while (oldlocal && TREE_CODE (oldlocal) == VAR_DECL && DECL_DEAD_FOR_LOCAL (oldlocal)) oldlocal = DECL_SHADOWED_FOR_VAR (oldlocal); if (oldlocal == NULL_TREE) oldlocal = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (d)); } /* If this is an extern function declaration, see if we have a global definition or declaration for the function. */ if (oldlocal == NULL_TREE && DECL_EXTERNAL (x) && oldglobal != NULL_TREE && TREE_CODE (x) == FUNCTION_DECL && TREE_CODE (oldglobal) == FUNCTION_DECL) { /* We have one. Their types must agree. */ if (decls_match (x, oldglobal)) /* OK */; else { warning (0, "extern declaration of %q#D doesn't match", x); warning (0, "global declaration %q+#D", oldglobal); } } /* If we have a local external declaration, and no file-scope declaration has yet been seen, then if we later have a file-scope decl it must not be static. */ if (oldlocal == NULL_TREE && oldglobal == NULL_TREE && DECL_EXTERNAL (x) && TREE_PUBLIC (x)) TREE_PUBLIC (name) = 1; /* Warn if shadowing an argument at the top level of the body. */ if (oldlocal != NULL_TREE && !DECL_EXTERNAL (x) /* Inline decls shadow nothing. */ && !DECL_FROM_INLINE (x) && TREE_CODE (oldlocal) == PARM_DECL /* Don't check the `this' parameter. */ && !DECL_ARTIFICIAL (oldlocal)) { bool err = false; /* Don't complain if it's from an enclosing function. */ if (DECL_CONTEXT (oldlocal) == current_function_decl && TREE_CODE (x) != PARM_DECL) { /* Go to where the parms should be and see if we find them there. */ struct cp_binding_level *b = current_binding_level->level_chain; if (FUNCTION_NEEDS_BODY_BLOCK (current_function_decl)) /* Skip the ctor/dtor cleanup level. */ b = b->level_chain; /* ARM $8.3 */ if (b->kind == sk_function_parms) { error ("declaration of %q#D shadows a parameter", x); err = true; } } if (warn_shadow && !err) { warning (OPT_Wshadow, "declaration of %q#D shadows a parameter", x); warning (OPT_Wshadow, "%Jshadowed declaration is here", oldlocal); } } /* Maybe warn if shadowing something else. */ else if (warn_shadow && !DECL_EXTERNAL (x) /* No shadow warnings for internally generated vars. */ && ! DECL_ARTIFICIAL (x) /* No shadow warnings for vars made for inlining. */ && ! DECL_FROM_INLINE (x)) { tree member; if (current_class_ptr) member = lookup_member (current_class_type, name, /*protect=*/0, /*want_type=*/false); else member = NULL_TREE; if (member && !TREE_STATIC (member)) { /* Location of previous decl is not useful in this case. */ warning (OPT_Wshadow, "declaration of %qD shadows a member of 'this'", x); } else if (oldlocal != NULL_TREE && TREE_CODE (oldlocal) == VAR_DECL) { warning (OPT_Wshadow, "declaration of %qD shadows a previous local", x); warning (OPT_Wshadow, "%Jshadowed declaration is here", oldlocal); } else if (oldglobal != NULL_TREE && TREE_CODE (oldglobal) == VAR_DECL) /* XXX shadow warnings in outer-more namespaces */ { warning (OPT_Wshadow, "declaration of %qD shadows a global declaration", x); warning (OPT_Wshadow, "%Jshadowed declaration is here", oldglobal); } } } if (TREE_CODE (x) == VAR_DECL) maybe_register_incomplete_var (x); } if (need_new_binding) add_decl_to_level (x, DECL_NAMESPACE_SCOPE_P (x) ? NAMESPACE_LEVEL (CP_DECL_CONTEXT (x)) : current_binding_level); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, x); } /* Record a decl-node X as belonging to the current lexical scope. */ tree pushdecl (tree x) { return pushdecl_maybe_friend (x, false); } /* Enter DECL into the symbol table, if that's appropriate. Returns DECL, or a modified version thereof. */ tree maybe_push_decl (tree decl) { tree type = TREE_TYPE (decl); /* Add this decl to the current binding level, but not if it comes from another scope, e.g. a static member variable. TEM may equal DECL or it may be a previous decl of the same name. */ if (decl == error_mark_node || (TREE_CODE (decl) != PARM_DECL && DECL_CONTEXT (decl) != NULL_TREE /* Definitions of namespace members outside their namespace are possible. */ && TREE_CODE (DECL_CONTEXT (decl)) != NAMESPACE_DECL) || (TREE_CODE (decl) == TEMPLATE_DECL && !namespace_bindings_p ()) || TREE_CODE (type) == UNKNOWN_TYPE /* The declaration of a template specialization does not affect the functions available for overload resolution, so we do not call pushdecl. */ || (TREE_CODE (decl) == FUNCTION_DECL && DECL_TEMPLATE_SPECIALIZATION (decl))) return decl; else return pushdecl (decl); } /* Bind DECL to ID in the current_binding_level, assumed to be a local binding level. If PUSH_USING is set in FLAGS, we know that DECL doesn't really belong to this binding level, that it got here through a using-declaration. */ void push_local_binding (tree id, tree decl, int flags) { struct cp_binding_level *b; /* Skip over any local classes. This makes sense if we call push_local_binding with a friend decl of a local class. */ b = innermost_nonclass_level (); if (lookup_name_innermost_nonclass_level (id)) { /* Supplement the existing binding. */ if (!supplement_binding (IDENTIFIER_BINDING (id), decl)) /* It didn't work. Something else must be bound at this level. Do not add DECL to the list of things to pop later. */ return; } else /* Create a new binding. */ push_binding (id, decl, b); if (TREE_CODE (decl) == OVERLOAD || (flags & PUSH_USING)) /* We must put the OVERLOAD into a TREE_LIST since the TREE_CHAIN of an OVERLOAD is already used. Similarly for decls that got here through a using-declaration. */ decl = build_tree_list (NULL_TREE, decl); /* And put DECL on the list of things declared by the current binding level. */ add_decl_to_level (decl, b); } /* Check to see whether or not DECL is a variable that would have been in scope under the ARM, but is not in scope under the ANSI/ISO standard. If so, issue an error message. If name lookup would work in both cases, but return a different result, this function returns the result of ANSI/ISO lookup. Otherwise, it returns DECL. */ tree check_for_out_of_scope_variable (tree decl) { tree shadowed; /* We only care about out of scope variables. */ if (!(TREE_CODE (decl) == VAR_DECL && DECL_DEAD_FOR_LOCAL (decl))) return decl; shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (decl) ? DECL_SHADOWED_FOR_VAR (decl) : NULL_TREE ; while (shadowed != NULL_TREE && TREE_CODE (shadowed) == VAR_DECL && DECL_DEAD_FOR_LOCAL (shadowed)) shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (shadowed) ? DECL_SHADOWED_FOR_VAR (shadowed) : NULL_TREE; if (!shadowed) shadowed = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (decl)); if (shadowed) { if (!DECL_ERROR_REPORTED (decl)) { warning (0, "name lookup of %qD changed", DECL_NAME (decl)); warning (0, " matches this %q+D under ISO standard rules", shadowed); warning (0, " matches this %q+D under old rules", decl); DECL_ERROR_REPORTED (decl) = 1; } return shadowed; } /* If we have already complained about this declaration, there's no need to do it again. */ if (DECL_ERROR_REPORTED (decl)) return decl; DECL_ERROR_REPORTED (decl) = 1; if (TREE_TYPE (decl) == error_mark_node) return decl; if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) { error ("name lookup of %qD changed for new ISO % scoping", DECL_NAME (decl)); error (" cannot use obsolete binding at %q+D because " "it has a destructor", decl); return error_mark_node; } else { pedwarn ("name lookup of %qD changed for new ISO % scoping", DECL_NAME (decl)); pedwarn (" using obsolete binding at %q+D", decl); } return decl; } /* true means unconditionally make a BLOCK for the next level pushed. */ static bool keep_next_level_flag; static int binding_depth = 0; static int is_class_level = 0; static void indent (int depth) { int i; for (i = 0; i < depth * 2; i++) putc (' ', stderr); } /* Return a string describing the kind of SCOPE we have. */ static const char * cxx_scope_descriptor (cxx_scope *scope) { /* The order of this table must match the "scope_kind" enumerators. */ static const char* scope_kind_names[] = { "block-scope", "cleanup-scope", "try-scope", "catch-scope", "for-scope", "function-parameter-scope", "class-scope", "namespace-scope", "template-parameter-scope", "template-explicit-spec-scope" }; const scope_kind kind = scope->explicit_spec_p ? sk_template_spec : scope->kind; return scope_kind_names[kind]; } /* Output a debugging information about SCOPE when performing ACTION at LINE. */ static void cxx_scope_debug (cxx_scope *scope, int line, const char *action) { const char *desc = cxx_scope_descriptor (scope); if (scope->this_entity) verbatim ("%s %s(%E) %p %d\n", action, desc, scope->this_entity, (void *) scope, line); else verbatim ("%s %s %p %d\n", action, desc, (void *) scope, line); } /* Return the estimated initial size of the hashtable of a NAMESPACE scope. */ static inline size_t namespace_scope_ht_size (tree ns) { tree name = DECL_NAME (ns); return name == std_identifier ? NAMESPACE_STD_HT_SIZE : (name == global_scope_name ? GLOBAL_SCOPE_HT_SIZE : NAMESPACE_ORDINARY_HT_SIZE); } /* A chain of binding_level structures awaiting reuse. */ static GTY((deletable)) struct cp_binding_level *free_binding_level; /* Insert SCOPE as the innermost binding level. */ void push_binding_level (struct cp_binding_level *scope) { /* Add it to the front of currently active scopes stack. */ scope->level_chain = current_binding_level; current_binding_level = scope; keep_next_level_flag = false; if (ENABLE_SCOPE_CHECKING) { scope->binding_depth = binding_depth; indent (binding_depth); cxx_scope_debug (scope, input_line, "push"); is_class_level = 0; binding_depth++; } } /* Create a new KIND scope and make it the top of the active scopes stack. ENTITY is the scope of the associated C++ entity (namespace, class, function); it is NULL otherwise. */ cxx_scope * begin_scope (scope_kind kind, tree entity) { cxx_scope *scope; /* Reuse or create a struct for this binding level. */ if (!ENABLE_SCOPE_CHECKING && free_binding_level) { scope = free_binding_level; memset (scope, 0, sizeof (cxx_scope)); free_binding_level = scope->level_chain; } else scope = GGC_CNEW (cxx_scope); scope->this_entity = entity; scope->more_cleanups_ok = true; switch (kind) { case sk_cleanup: scope->keep = true; break; case sk_template_spec: scope->explicit_spec_p = true; kind = sk_template_parms; /* Fall through. */ case sk_template_parms: case sk_block: case sk_try: case sk_catch: case sk_for: case sk_class: case sk_function_parms: case sk_omp: scope->keep = keep_next_level_flag; break; case sk_namespace: NAMESPACE_LEVEL (entity) = scope; scope->static_decls = VEC_alloc (tree, gc, DECL_NAME (entity) == std_identifier || DECL_NAME (entity) == global_scope_name ? 200 : 10); break; default: /* Should not happen. */ gcc_unreachable (); break; } scope->kind = kind; push_binding_level (scope); return scope; } /* We're about to leave current scope. Pop the top of the stack of currently active scopes. Return the enclosing scope, now active. */ cxx_scope * leave_scope (void) { cxx_scope *scope = current_binding_level; if (scope->kind == sk_namespace && class_binding_level) current_binding_level = class_binding_level; /* We cannot leave a scope, if there are none left. */ if (NAMESPACE_LEVEL (global_namespace)) gcc_assert (!global_scope_p (scope)); if (ENABLE_SCOPE_CHECKING) { indent (--binding_depth); cxx_scope_debug (scope, input_line, "leave"); if (is_class_level != (scope == class_binding_level)) { indent (binding_depth); verbatim ("XXX is_class_level != (current_scope == class_scope)\n"); } is_class_level = 0; } /* Move one nesting level up. */ current_binding_level = scope->level_chain; /* Namespace-scopes are left most probably temporarily, not completely; they can be reopened later, e.g. in namespace-extension or any name binding activity that requires us to resume a namespace. For classes, we cache some binding levels. For other scopes, we just make the structure available for reuse. */ if (scope->kind != sk_namespace && scope->kind != sk_class) { scope->level_chain = free_binding_level; gcc_assert (!ENABLE_SCOPE_CHECKING || scope->binding_depth == binding_depth); free_binding_level = scope; } /* Find the innermost enclosing class scope, and reset CLASS_BINDING_LEVEL appropriately. */ if (scope->kind == sk_class) { class_binding_level = NULL; for (scope = current_binding_level; scope; scope = scope->level_chain) if (scope->kind == sk_class) { class_binding_level = scope; break; } } return current_binding_level; } static void resume_scope (struct cp_binding_level* b) { /* Resuming binding levels is meant only for namespaces, and those cannot nest into classes. */ gcc_assert (!class_binding_level); /* Also, resuming a non-directly nested namespace is a no-no. */ gcc_assert (b->level_chain == current_binding_level); current_binding_level = b; if (ENABLE_SCOPE_CHECKING) { b->binding_depth = binding_depth; indent (binding_depth); cxx_scope_debug (b, input_line, "resume"); is_class_level = 0; binding_depth++; } } /* Return the innermost binding level that is not for a class scope. */ static cxx_scope * innermost_nonclass_level (void) { cxx_scope *b; b = current_binding_level; while (b->kind == sk_class) b = b->level_chain; return b; } /* We're defining an object of type TYPE. If it needs a cleanup, but we're not allowed to add any more objects with cleanups to the current scope, create a new binding level. */ void maybe_push_cleanup_level (tree type) { if (type != error_mark_node && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type) && current_binding_level->more_cleanups_ok == 0) { begin_scope (sk_cleanup, NULL); current_binding_level->statement_list = push_stmt_list (); } } /* Nonzero if we are currently in the global binding level. */ int global_bindings_p (void) { return global_scope_p (current_binding_level); } /* True if we are currently in a toplevel binding level. This means either the global binding level or a namespace in a toplevel binding level. Since there are no non-toplevel namespace levels, this really means any namespace or template parameter level. We also include a class whose context is toplevel. */ bool toplevel_bindings_p (void) { struct cp_binding_level *b = innermost_nonclass_level (); return b->kind == sk_namespace || b->kind == sk_template_parms; } /* True if this is a namespace scope, or if we are defining a class which is itself at namespace scope, or whose enclosing class is such a class, etc. */ bool namespace_bindings_p (void) { struct cp_binding_level *b = innermost_nonclass_level (); return b->kind == sk_namespace; } /* True if the current level needs to have a BLOCK made. */ bool kept_level_p (void) { return (current_binding_level->blocks != NULL_TREE || current_binding_level->keep || current_binding_level->kind == sk_cleanup || current_binding_level->names != NULL_TREE); } /* Returns the kind of the innermost scope. */ scope_kind innermost_scope_kind (void) { return current_binding_level->kind; } /* Returns true if this scope was created to store template parameters. */ bool template_parm_scope_p (void) { return innermost_scope_kind () == sk_template_parms; } /* If KEEP is true, make a BLOCK node for the next binding level, unconditionally. Otherwise, use the normal logic to decide whether or not to create a BLOCK. */ void keep_next_level (bool keep) { keep_next_level_flag = keep; } /* Return the list of declarations of the current level. Note that this list is in reverse order unless/until you nreverse it; and when you do nreverse it, you must store the result back using `storedecls' or you will lose. */ tree getdecls (void) { return current_binding_level->names; } /* For debugging. */ static int no_print_functions = 0; static int no_print_builtins = 0; static void print_binding_level (struct cp_binding_level* lvl) { tree t; int i = 0, len; fprintf (stderr, " blocks=%p", (void *) lvl->blocks); if (lvl->more_cleanups_ok) fprintf (stderr, " more-cleanups-ok"); if (lvl->have_cleanups) fprintf (stderr, " have-cleanups"); fprintf (stderr, "\n"); if (lvl->names) { fprintf (stderr, " names:\t"); /* We can probably fit 3 names to a line? */ for (t = lvl->names; t; t = TREE_CHAIN (t)) { if (no_print_functions && (TREE_CODE (t) == FUNCTION_DECL)) continue; if (no_print_builtins && (TREE_CODE (t) == TYPE_DECL) && DECL_IS_BUILTIN (t)) continue; /* Function decls tend to have longer names. */ if (TREE_CODE (t) == FUNCTION_DECL) len = 3; else len = 2; i += len; if (i > 6) { fprintf (stderr, "\n\t"); i = len; } print_node_brief (stderr, "", t, 0); if (t == error_mark_node) break; } if (i) fprintf (stderr, "\n"); } if (VEC_length (cp_class_binding, lvl->class_shadowed)) { size_t i; cp_class_binding *b; fprintf (stderr, " class-shadowed:"); for (i = 0; VEC_iterate(cp_class_binding, lvl->class_shadowed, i, b); ++i) fprintf (stderr, " %s ", IDENTIFIER_POINTER (b->identifier)); fprintf (stderr, "\n"); } if (lvl->type_shadowed) { fprintf (stderr, " type-shadowed:"); for (t = lvl->type_shadowed; t; t = TREE_CHAIN (t)) { fprintf (stderr, " %s ", IDENTIFIER_POINTER (TREE_PURPOSE (t))); } fprintf (stderr, "\n"); } } void print_other_binding_stack (struct cp_binding_level *stack) { struct cp_binding_level *level; for (level = stack; !global_scope_p (level); level = level->level_chain) { fprintf (stderr, "binding level %p\n", (void *) level); print_binding_level (level); } } void print_binding_stack (void) { struct cp_binding_level *b; fprintf (stderr, "current_binding_level=%p\n" "class_binding_level=%p\n" "NAMESPACE_LEVEL (global_namespace)=%p\n", (void *) current_binding_level, (void *) class_binding_level, (void *) NAMESPACE_LEVEL (global_namespace)); if (class_binding_level) { for (b = class_binding_level; b; b = b->level_chain) if (b == current_binding_level) break; if (b) b = class_binding_level; else b = current_binding_level; } else b = current_binding_level; print_other_binding_stack (b); fprintf (stderr, "global:\n"); print_binding_level (NAMESPACE_LEVEL (global_namespace)); } /* Return the type associated with id. */ tree identifier_type_value (tree id) { timevar_push (TV_NAME_LOOKUP); /* There is no type with that name, anywhere. */ if (REAL_IDENTIFIER_TYPE_VALUE (id) == NULL_TREE) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, NULL_TREE); /* This is not the type marker, but the real thing. */ if (REAL_IDENTIFIER_TYPE_VALUE (id) != global_type_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, REAL_IDENTIFIER_TYPE_VALUE (id)); /* Have to search for it. It must be on the global level, now. Ask lookup_name not to return non-types. */ id = lookup_name_real (id, 2, 1, /*block_p=*/true, 0, LOOKUP_COMPLAIN); if (id) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_TYPE (id)); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, NULL_TREE); } /* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++. */ tree identifier_global_value (tree t) { return IDENTIFIER_GLOBAL_VALUE (t); } /* Push a definition of struct, union or enum tag named ID. into binding_level B. DECL is a TYPE_DECL for the type. We assume that the tag ID is not already defined. */ static void set_identifier_type_value_with_scope (tree id, tree decl, cxx_scope *b) { tree type; if (b->kind != sk_namespace) { /* Shadow the marker, not the real thing, so that the marker gets restored later. */ tree old_type_value = REAL_IDENTIFIER_TYPE_VALUE (id); b->type_shadowed = tree_cons (id, old_type_value, b->type_shadowed); type = decl ? TREE_TYPE (decl) : NULL_TREE; TREE_TYPE (b->type_shadowed) = type; } else { cxx_binding *binding = binding_for_name (NAMESPACE_LEVEL (current_namespace), id); gcc_assert (decl); if (binding->value) supplement_binding (binding, decl); else binding->value = decl; /* Store marker instead of real type. */ type = global_type_node; } SET_IDENTIFIER_TYPE_VALUE (id, type); } /* As set_identifier_type_value_with_scope, but using current_binding_level. */ void set_identifier_type_value (tree id, tree decl) { set_identifier_type_value_with_scope (id, decl, current_binding_level); } /* Return the name for the constructor (or destructor) for the specified class TYPE. When given a template, this routine doesn't lose the specialization. */ static inline tree constructor_name_full (tree type) { return TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type)); } /* Return the name for the constructor (or destructor) for the specified class. When given a template, return the plain unspecialized name. */ tree constructor_name (tree type) { tree name; name = constructor_name_full (type); if (IDENTIFIER_TEMPLATE (name)) name = IDENTIFIER_TEMPLATE (name); return name; } /* Returns TRUE if NAME is the name for the constructor for TYPE. */ bool constructor_name_p (tree name, tree type) { tree ctor_name; if (!name) return false; if (TREE_CODE (name) != IDENTIFIER_NODE) return false; ctor_name = constructor_name_full (type); if (name == ctor_name) return true; if (IDENTIFIER_TEMPLATE (ctor_name) && name == IDENTIFIER_TEMPLATE (ctor_name)) return true; return false; } /* Counter used to create anonymous type names. */ static GTY(()) int anon_cnt; /* Return an IDENTIFIER which can be used as a name for anonymous structs and unions. */ tree make_anon_name (void) { char buf[32]; sprintf (buf, ANON_AGGRNAME_FORMAT, anon_cnt++); return get_identifier (buf); } /* Return (from the stack of) the BINDING, if any, established at SCOPE. */ static inline cxx_binding * find_binding (cxx_scope *scope, cxx_binding *binding) { timevar_push (TV_NAME_LOOKUP); for (; binding != NULL; binding = binding->previous) if (binding->scope == scope) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, binding); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, (cxx_binding *)0); } /* Return the binding for NAME in SCOPE, if any. Otherwise, return NULL. */ static inline cxx_binding * cxx_scope_find_binding_for_name (cxx_scope *scope, tree name) { cxx_binding *b = IDENTIFIER_NAMESPACE_BINDINGS (name); if (b) { /* Fold-in case where NAME is used only once. */ if (scope == b->scope && b->previous == NULL) return b; return find_binding (scope, b); } return NULL; } /* Always returns a binding for name in scope. If no binding is found, make a new one. */ static cxx_binding * binding_for_name (cxx_scope *scope, tree name) { cxx_binding *result; result = cxx_scope_find_binding_for_name (scope, name); if (result) return result; /* Not found, make a new one. */ result = cxx_binding_make (NULL, NULL); result->previous = IDENTIFIER_NAMESPACE_BINDINGS (name); result->scope = scope; result->is_local = false; result->value_is_inherited = false; IDENTIFIER_NAMESPACE_BINDINGS (name) = result; return result; } /* Insert another USING_DECL into the current binding level, returning this declaration. If this is a redeclaration, do nothing, and return NULL_TREE if this not in namespace scope (in namespace scope, a using decl might extend any previous bindings). */ static tree push_using_decl (tree scope, tree name) { tree decl; timevar_push (TV_NAME_LOOKUP); gcc_assert (TREE_CODE (scope) == NAMESPACE_DECL); gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE); for (decl = current_binding_level->usings; decl; decl = TREE_CHAIN (decl)) if (USING_DECL_SCOPE (decl) == scope && DECL_NAME (decl) == name) break; if (decl) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, namespace_bindings_p () ? decl : NULL_TREE); decl = build_lang_decl (USING_DECL, name, NULL_TREE); USING_DECL_SCOPE (decl) = scope; TREE_CHAIN (decl) = current_binding_level->usings; current_binding_level->usings = decl; POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, decl); } /* Same as pushdecl, but define X in binding-level LEVEL. We rely on the caller to set DECL_CONTEXT properly. */ tree pushdecl_with_scope (tree x, cxx_scope *level, bool is_friend) { struct cp_binding_level *b; tree function_decl = current_function_decl; timevar_push (TV_NAME_LOOKUP); current_function_decl = NULL_TREE; if (level->kind == sk_class) { b = class_binding_level; class_binding_level = level; pushdecl_class_level (x); class_binding_level = b; } else { b = current_binding_level; current_binding_level = level; x = pushdecl_maybe_friend (x, is_friend); current_binding_level = b; } current_function_decl = function_decl; POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, x); } /* DECL is a FUNCTION_DECL for a non-member function, which may have other definitions already in place. We get around this by making the value of the identifier point to a list of all the things that want to be referenced by that name. It is then up to the users of that name to decide what to do with that list. DECL may also be a TEMPLATE_DECL, with a FUNCTION_DECL in its DECL_TEMPLATE_RESULT. It is dealt with the same way. FLAGS is a bitwise-or of the following values: PUSH_LOCAL: Bind DECL in the current scope, rather than at namespace scope. PUSH_USING: DECL is being pushed as the result of a using declaration. IS_FRIEND is true if this is a friend declaration. The value returned may be a previous declaration if we guessed wrong about what language DECL should belong to (C or C++). Otherwise, it's always DECL (and never something that's not a _DECL). */ static tree push_overloaded_decl (tree decl, int flags, bool is_friend) { tree name = DECL_NAME (decl); tree old; tree new_binding; int doing_global = (namespace_bindings_p () || !(flags & PUSH_LOCAL)); timevar_push (TV_NAME_LOOKUP); if (doing_global) old = namespace_binding (name, DECL_CONTEXT (decl)); else old = lookup_name_innermost_nonclass_level (name); if (old) { if (TREE_CODE (old) == TYPE_DECL && DECL_ARTIFICIAL (old)) { tree t = TREE_TYPE (old); if (IS_AGGR_TYPE (t) && warn_shadow && (! DECL_IN_SYSTEM_HEADER (decl) || ! DECL_IN_SYSTEM_HEADER (old))) warning (0, "%q#D hides constructor for %q#T", decl, t); old = NULL_TREE; } else if (is_overloaded_fn (old)) { tree tmp; for (tmp = old; tmp; tmp = OVL_NEXT (tmp)) { tree fn = OVL_CURRENT (tmp); tree dup; if (TREE_CODE (tmp) == OVERLOAD && OVL_USED (tmp) && !(flags & PUSH_USING) && compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)), TYPE_ARG_TYPES (TREE_TYPE (decl))) && ! decls_match (fn, decl)) error ("%q#D conflicts with previous using declaration %q#D", decl, fn); dup = duplicate_decls (decl, fn, is_friend); /* If DECL was a redeclaration of FN -- even an invalid one -- pass that information along to our caller. */ if (dup == fn || dup == error_mark_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, dup); } /* We don't overload implicit built-ins. duplicate_decls() may fail to merge the decls if the new decl is e.g. a template function. */ if (TREE_CODE (old) == FUNCTION_DECL && DECL_ANTICIPATED (old) && !DECL_HIDDEN_FRIEND_P (old)) old = NULL; } else if (old == error_mark_node) /* Ignore the undefined symbol marker. */ old = NULL_TREE; else { error ("previous non-function declaration %q+#D", old); error ("conflicts with function declaration %q#D", decl); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, decl); } } if (old || TREE_CODE (decl) == TEMPLATE_DECL /* If it's a using declaration, we always need to build an OVERLOAD, because it's the only way to remember that the declaration comes from 'using', and have the lookup behave correctly. */ || (flags & PUSH_USING)) { if (old && TREE_CODE (old) != OVERLOAD) new_binding = ovl_cons (decl, ovl_cons (old, NULL_TREE)); else new_binding = ovl_cons (decl, old); if (flags & PUSH_USING) OVL_USED (new_binding) = 1; } else /* NAME is not ambiguous. */ new_binding = decl; if (doing_global) set_namespace_binding (name, current_namespace, new_binding); else { /* We only create an OVERLOAD if there was a previous binding at this level, or if decl is a template. In the former case, we need to remove the old binding and replace it with the new binding. We must also run through the NAMES on the binding level where the name was bound to update the chain. */ if (TREE_CODE (new_binding) == OVERLOAD && old) { tree *d; for (d = &IDENTIFIER_BINDING (name)->scope->names; *d; d = &TREE_CHAIN (*d)) if (*d == old || (TREE_CODE (*d) == TREE_LIST && TREE_VALUE (*d) == old)) { if (TREE_CODE (*d) == TREE_LIST) /* Just replace the old binding with the new. */ TREE_VALUE (*d) = new_binding; else /* Build a TREE_LIST to wrap the OVERLOAD. */ *d = tree_cons (NULL_TREE, new_binding, TREE_CHAIN (*d)); /* And update the cxx_binding node. */ IDENTIFIER_BINDING (name)->value = new_binding; POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, decl); } /* We should always find a previous binding in this case. */ gcc_unreachable (); } /* Install the new binding. */ push_local_binding (name, new_binding, flags); } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, decl); } /* Check a non-member using-declaration. Return the name and scope being used, and the USING_DECL, or NULL_TREE on failure. */ static tree validate_nonmember_using_decl (tree decl, tree scope, tree name) { /* [namespace.udecl] A using-declaration for a class member shall be a member-declaration. */ if (TYPE_P (scope)) { error ("%qT is not a namespace", scope); return NULL_TREE; } else if (scope == error_mark_node) return NULL_TREE; if (TREE_CODE (decl) == TEMPLATE_ID_EXPR) { /* 7.3.3/5 A using-declaration shall not name a template-id. */ error ("a using-declaration cannot specify a template-id. " "Try %", name); return NULL_TREE; } if (TREE_CODE (decl) == NAMESPACE_DECL) { error ("namespace %qD not allowed in using-declaration", decl); return NULL_TREE; } if (TREE_CODE (decl) == SCOPE_REF) { /* It's a nested name with template parameter dependent scope. This can only be using-declaration for class member. */ error ("%qT is not a namespace", TREE_OPERAND (decl, 0)); return NULL_TREE; } if (is_overloaded_fn (decl)) decl = get_first_fn (decl); gcc_assert (DECL_P (decl)); /* Make a USING_DECL. */ return push_using_decl (scope, name); } /* Process local and global using-declarations. */ static void do_nonmember_using_decl (tree scope, tree name, tree oldval, tree oldtype, tree *newval, tree *newtype) { struct scope_binding decls = EMPTY_SCOPE_BINDING; *newval = *newtype = NULL_TREE; if (!qualified_lookup_using_namespace (name, scope, &decls, 0)) /* Lookup error */ return; if (!decls.value && !decls.type) { error ("%qD not declared", name); return; } /* Shift the old and new bindings around so we're comparing class and enumeration names to each other. */ if (oldval && DECL_IMPLICIT_TYPEDEF_P (oldval)) { oldtype = oldval; oldval = NULL_TREE; } if (decls.value && DECL_IMPLICIT_TYPEDEF_P (decls.value)) { decls.type = decls.value; decls.value = NULL_TREE; } /* It is impossible to overload a built-in function; any explicit declaration eliminates the built-in declaration. So, if OLDVAL is a built-in, then we can just pretend it isn't there. */ if (oldval && TREE_CODE (oldval) == FUNCTION_DECL && DECL_ANTICIPATED (oldval) && !DECL_HIDDEN_FRIEND_P (oldval)) oldval = NULL_TREE; if (decls.value) { /* Check for using functions. */ if (is_overloaded_fn (decls.value)) { tree tmp, tmp1; if (oldval && !is_overloaded_fn (oldval)) { error ("%qD is already declared in this scope", name); oldval = NULL_TREE; } *newval = oldval; for (tmp = decls.value; tmp; tmp = OVL_NEXT (tmp)) { tree new_fn = OVL_CURRENT (tmp); /* [namespace.udecl] If a function declaration in namespace scope or block scope has the same name and the same parameter types as a function introduced by a using declaration the program is ill-formed. */ for (tmp1 = oldval; tmp1; tmp1 = OVL_NEXT (tmp1)) { tree old_fn = OVL_CURRENT (tmp1); if (new_fn == old_fn) /* The function already exists in the current namespace. */ break; else if (OVL_USED (tmp1)) continue; /* this is a using decl */ else if (compparms (TYPE_ARG_TYPES (TREE_TYPE (new_fn)), TYPE_ARG_TYPES (TREE_TYPE (old_fn)))) { gcc_assert (!DECL_ANTICIPATED (old_fn) || DECL_HIDDEN_FRIEND_P (old_fn)); /* There was already a non-using declaration in this scope with the same parameter types. If both are the same extern "C" functions, that's ok. */ if (decls_match (new_fn, old_fn)) break; else { error ("%qD is already declared in this scope", name); break; } } } /* If we broke out of the loop, there's no reason to add this function to the using declarations for this scope. */ if (tmp1) continue; /* If we are adding to an existing OVERLOAD, then we no longer know the type of the set of functions. */ if (*newval && TREE_CODE (*newval) == OVERLOAD) TREE_TYPE (*newval) = unknown_type_node; /* Add this new function to the set. */ *newval = build_overload (OVL_CURRENT (tmp), *newval); /* If there is only one function, then we use its type. (A using-declaration naming a single function can be used in contexts where overload resolution cannot be performed.) */ if (TREE_CODE (*newval) != OVERLOAD) { *newval = ovl_cons (*newval, NULL_TREE); TREE_TYPE (*newval) = TREE_TYPE (OVL_CURRENT (tmp)); } OVL_USED (*newval) = 1; } } else { *newval = decls.value; if (oldval && !decls_match (*newval, oldval)) error ("%qD is already declared in this scope", name); } } else *newval = oldval; if (decls.type && TREE_CODE (decls.type) == TREE_LIST) { error ("reference to %qD is ambiguous", name); print_candidates (decls.type); } else { *newtype = decls.type; if (oldtype && *newtype && !decls_match (oldtype, *newtype)) error ("%qD is already declared in this scope", name); } /* If *newval is empty, shift any class or enumeration name down. */ if (!*newval) { *newval = *newtype; *newtype = NULL_TREE; } } /* Process a using-declaration at function scope. */ void do_local_using_decl (tree decl, tree scope, tree name) { tree oldval, oldtype, newval, newtype; tree orig_decl = decl; decl = validate_nonmember_using_decl (decl, scope, name); if (decl == NULL_TREE) return; if (building_stmt_tree () && at_function_scope_p ()) add_decl_expr (decl); oldval = lookup_name_innermost_nonclass_level (name); oldtype = lookup_type_current_level (name); do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype); if (newval) { if (is_overloaded_fn (newval)) { tree fn, term; /* We only need to push declarations for those functions that were not already bound in the current level. The old value might be NULL_TREE, it might be a single function, or an OVERLOAD. */ if (oldval && TREE_CODE (oldval) == OVERLOAD) term = OVL_FUNCTION (oldval); else term = oldval; for (fn = newval; fn && OVL_CURRENT (fn) != term; fn = OVL_NEXT (fn)) push_overloaded_decl (OVL_CURRENT (fn), PUSH_LOCAL | PUSH_USING, false); } else push_local_binding (name, newval, PUSH_USING); } if (newtype) { push_local_binding (name, newtype, PUSH_USING); set_identifier_type_value (name, newtype); } /* Emit debug info. */ if (!processing_template_decl) cp_emit_debug_info_for_using (orig_decl, current_scope()); } /* Returns true if ROOT (a namespace, class, or function) encloses CHILD. CHILD may be either a class type or a namespace. */ bool is_ancestor (tree root, tree child) { gcc_assert ((TREE_CODE (root) == NAMESPACE_DECL || TREE_CODE (root) == FUNCTION_DECL || CLASS_TYPE_P (root))); gcc_assert ((TREE_CODE (child) == NAMESPACE_DECL || CLASS_TYPE_P (child))); /* The global namespace encloses everything. */ if (root == global_namespace) return true; while (true) { /* If we've run out of scopes, stop. */ if (!child) return false; /* If we've reached the ROOT, it encloses CHILD. */ if (root == child) return true; /* Go out one level. */ if (TYPE_P (child)) child = TYPE_NAME (child); child = DECL_CONTEXT (child); } } /* Enter the class or namespace scope indicated by T suitable for name lookup. T can be arbitrary scope, not necessary nested inside the current scope. Returns a non-null scope to pop iff pop_scope should be called later to exit this scope. */ tree push_scope (tree t) { if (TREE_CODE (t) == NAMESPACE_DECL) push_decl_namespace (t); else if (CLASS_TYPE_P (t)) { if (!at_class_scope_p () || !same_type_p (current_class_type, t)) push_nested_class (t); else /* T is the same as the current scope. There is therefore no need to re-enter the scope. Since we are not actually pushing a new scope, our caller should not call pop_scope. */ t = NULL_TREE; } return t; } /* Leave scope pushed by push_scope. */ void pop_scope (tree t) { if (TREE_CODE (t) == NAMESPACE_DECL) pop_decl_namespace (); else if CLASS_TYPE_P (t) pop_nested_class (); } /* Subroutine of push_inner_scope. */ static void push_inner_scope_r (tree outer, tree inner) { tree prev; if (outer == inner || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner))) return; prev = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner)); if (outer != prev) push_inner_scope_r (outer, prev); if (TREE_CODE (inner) == NAMESPACE_DECL) { struct cp_binding_level *save_template_parm = 0; /* Temporary take out template parameter scopes. They are saved in reversed order in save_template_parm. */ while (current_binding_level->kind == sk_template_parms) { struct cp_binding_level *b = current_binding_level; current_binding_level = b->level_chain; b->level_chain = save_template_parm; save_template_parm = b; } resume_scope (NAMESPACE_LEVEL (inner)); current_namespace = inner; /* Restore template parameter scopes. */ while (save_template_parm) { struct cp_binding_level *b = save_template_parm; save_template_parm = b->level_chain; b->level_chain = current_binding_level; current_binding_level = b; } } else pushclass (inner); } /* Enter the scope INNER from current scope. INNER must be a scope nested inside current scope. This works with both name lookup and pushing name into scope. In case a template parameter scope is present, namespace is pushed under the template parameter scope according to name lookup rule in 14.6.1/6. Return the former current scope suitable for pop_inner_scope. */ tree push_inner_scope (tree inner) { tree outer = current_scope (); if (!outer) outer = current_namespace; push_inner_scope_r (outer, inner); return outer; } /* Exit the current scope INNER back to scope OUTER. */ void pop_inner_scope (tree outer, tree inner) { if (outer == inner || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner))) return; while (outer != inner) { if (TREE_CODE (inner) == NAMESPACE_DECL) { struct cp_binding_level *save_template_parm = 0; /* Temporary take out template parameter scopes. They are saved in reversed order in save_template_parm. */ while (current_binding_level->kind == sk_template_parms) { struct cp_binding_level *b = current_binding_level; current_binding_level = b->level_chain; b->level_chain = save_template_parm; save_template_parm = b; } pop_namespace (); /* Restore template parameter scopes. */ while (save_template_parm) { struct cp_binding_level *b = save_template_parm; save_template_parm = b->level_chain; b->level_chain = current_binding_level; current_binding_level = b; } } else popclass (); inner = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner)); } } /* Do a pushlevel for class declarations. */ void pushlevel_class (void) { if (ENABLE_SCOPE_CHECKING) is_class_level = 1; class_binding_level = begin_scope (sk_class, current_class_type); } /* ...and a poplevel for class declarations. */ void poplevel_class (void) { struct cp_binding_level *level = class_binding_level; cp_class_binding *cb; size_t i; tree shadowed; timevar_push (TV_NAME_LOOKUP); gcc_assert (level != 0); /* If we're leaving a toplevel class, cache its binding level. */ if (current_class_depth == 1) previous_class_level = level; for (shadowed = level->type_shadowed; shadowed; shadowed = TREE_CHAIN (shadowed)) SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (shadowed), TREE_VALUE (shadowed)); /* Remove the bindings for all of the class-level declarations. */ if (level->class_shadowed) { for (i = 0; VEC_iterate (cp_class_binding, level->class_shadowed, i, cb); ++i) IDENTIFIER_BINDING (cb->identifier) = cb->base.previous; ggc_free (level->class_shadowed); level->class_shadowed = NULL; } /* Now, pop out of the binding level which we created up in the `pushlevel_class' routine. */ if (ENABLE_SCOPE_CHECKING) is_class_level = 1; leave_scope (); timevar_pop (TV_NAME_LOOKUP); } /* Set INHERITED_VALUE_BINDING_P on BINDING to true or false, as appropriate. DECL is the value to which a name has just been bound. CLASS_TYPE is the class in which the lookup occurred. */ static void set_inherited_value_binding_p (cxx_binding *binding, tree decl, tree class_type) { if (binding->value == decl && TREE_CODE (decl) != TREE_LIST) { tree context; if (TREE_CODE (decl) == OVERLOAD) context = CP_DECL_CONTEXT (OVL_CURRENT (decl)); else { gcc_assert (DECL_P (decl)); context = context_for_name_lookup (decl); } if (is_properly_derived_from (class_type, context)) INHERITED_VALUE_BINDING_P (binding) = 1; else INHERITED_VALUE_BINDING_P (binding) = 0; } else if (binding->value == decl) /* We only encounter a TREE_LIST when there is an ambiguity in the base classes. Such an ambiguity can be overridden by a definition in this class. */ INHERITED_VALUE_BINDING_P (binding) = 1; else INHERITED_VALUE_BINDING_P (binding) = 0; } /* Make the declaration of X appear in CLASS scope. */ bool pushdecl_class_level (tree x) { tree name; bool is_valid = true; timevar_push (TV_NAME_LOOKUP); /* Get the name of X. */ if (TREE_CODE (x) == OVERLOAD) name = DECL_NAME (get_first_fn (x)); else name = DECL_NAME (x); if (name) { is_valid = push_class_level_binding (name, x); if (TREE_CODE (x) == TYPE_DECL) set_identifier_type_value (name, x); } else if (ANON_AGGR_TYPE_P (TREE_TYPE (x))) { /* If X is an anonymous aggregate, all of its members are treated as if they were members of the class containing the aggregate, for naming purposes. */ tree f; for (f = TYPE_FIELDS (TREE_TYPE (x)); f; f = TREE_CHAIN (f)) { location_t save_location = input_location; input_location = DECL_SOURCE_LOCATION (f); if (!pushdecl_class_level (f)) is_valid = false; input_location = save_location; } } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, is_valid); } /* Return the BINDING (if any) for NAME in SCOPE, which is a class scope. If the value returned is non-NULL, and the PREVIOUS field is not set, callers must set the PREVIOUS field explicitly. */ static cxx_binding * get_class_binding (tree name, cxx_scope *scope) { tree class_type; tree type_binding; tree value_binding; cxx_binding *binding; class_type = scope->this_entity; /* Get the type binding. */ type_binding = lookup_member (class_type, name, /*protect=*/2, /*want_type=*/true); /* Get the value binding. */ value_binding = lookup_member (class_type, name, /*protect=*/2, /*want_type=*/false); if (value_binding && (TREE_CODE (value_binding) == TYPE_DECL || DECL_CLASS_TEMPLATE_P (value_binding) || (TREE_CODE (value_binding) == TREE_LIST && TREE_TYPE (value_binding) == error_mark_node && (TREE_CODE (TREE_VALUE (value_binding)) == TYPE_DECL)))) /* We found a type binding, even when looking for a non-type binding. This means that we already processed this binding above. */ ; else if (value_binding) { if (TREE_CODE (value_binding) == TREE_LIST && TREE_TYPE (value_binding) == error_mark_node) /* NAME is ambiguous. */ ; else if (BASELINK_P (value_binding)) /* NAME is some overloaded functions. */ value_binding = BASELINK_FUNCTIONS (value_binding); } /* If we found either a type binding or a value binding, create a new binding object. */ if (type_binding || value_binding) { binding = new_class_binding (name, value_binding, type_binding, scope); /* This is a class-scope binding, not a block-scope binding. */ LOCAL_BINDING_P (binding) = 0; set_inherited_value_binding_p (binding, value_binding, class_type); } else binding = NULL; return binding; } /* Make the declaration(s) of X appear in CLASS scope under the name NAME. Returns true if the binding is valid. */ bool push_class_level_binding (tree name, tree x) { cxx_binding *binding; tree decl = x; bool ok; timevar_push (TV_NAME_LOOKUP); /* The class_binding_level will be NULL if x is a template parameter name in a member template. */ if (!class_binding_level) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, true); if (name == error_mark_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, false); /* Check for invalid member names. */ gcc_assert (TYPE_BEING_DEFINED (current_class_type)); /* We could have been passed a tree list if this is an ambiguous declaration. If so, pull the declaration out because check_template_shadow will not handle a TREE_LIST. */ if (TREE_CODE (decl) == TREE_LIST && TREE_TYPE (decl) == error_mark_node) decl = TREE_VALUE (decl); check_template_shadow (decl); /* [class.mem] If T is the name of a class, then each of the following shall have a name different from T: -- every static data member of class T; -- every member of class T that is itself a type; -- every enumerator of every member of class T that is an enumerated type; -- every member of every anonymous union that is a member of class T. (Non-static data members were also forbidden to have the same name as T until TC1.) */ if ((TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == CONST_DECL || (TREE_CODE (x) == TYPE_DECL && !DECL_SELF_REFERENCE_P (x)) /* A data member of an anonymous union. */ || (TREE_CODE (x) == FIELD_DECL && DECL_CONTEXT (x) != current_class_type)) && DECL_NAME (x) == constructor_name (current_class_type)) { tree scope = context_for_name_lookup (x); if (TYPE_P (scope) && same_type_p (scope, current_class_type)) { error ("%qD has the same name as the class in which it is " "declared", x); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, false); } } /* Get the current binding for NAME in this class, if any. */ binding = IDENTIFIER_BINDING (name); if (!binding || binding->scope != class_binding_level) { binding = get_class_binding (name, class_binding_level); /* If a new binding was created, put it at the front of the IDENTIFIER_BINDING list. */ if (binding) { binding->previous = IDENTIFIER_BINDING (name); IDENTIFIER_BINDING (name) = binding; } } /* If there is already a binding, then we may need to update the current value. */ if (binding && binding->value) { tree bval = binding->value; tree old_decl = NULL_TREE; if (INHERITED_VALUE_BINDING_P (binding)) { /* If the old binding was from a base class, and was for a tag name, slide it over to make room for the new binding. The old binding is still visible if explicitly qualified with a class-key. */ if (TREE_CODE (bval) == TYPE_DECL && DECL_ARTIFICIAL (bval) && !(TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x))) { old_decl = binding->type; binding->type = bval; binding->value = NULL_TREE; INHERITED_VALUE_BINDING_P (binding) = 0; } else { old_decl = bval; /* Any inherited type declaration is hidden by the type declaration in the derived class. */ if (TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x)) binding->type = NULL_TREE; } } else if (TREE_CODE (x) == OVERLOAD && is_overloaded_fn (bval)) old_decl = bval; else if (TREE_CODE (x) == USING_DECL && TREE_CODE (bval) == USING_DECL) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, true); else if (TREE_CODE (x) == USING_DECL && is_overloaded_fn (bval)) old_decl = bval; else if (TREE_CODE (bval) == USING_DECL && is_overloaded_fn (x)) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, true); if (old_decl && binding->scope == class_binding_level) { binding->value = x; /* It is always safe to clear INHERITED_VALUE_BINDING_P here. This function is only used to register bindings from with the class definition itself. */ INHERITED_VALUE_BINDING_P (binding) = 0; POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, true); } } /* Note that we declared this value so that we can issue an error if this is an invalid redeclaration of a name already used for some other purpose. */ note_name_declared_in_class (name, decl); /* If we didn't replace an existing binding, put the binding on the stack of bindings for the identifier, and update the shadowed list. */ if (binding && binding->scope == class_binding_level) /* Supplement the existing binding. */ ok = supplement_binding (binding, decl); else { /* Create a new binding. */ push_binding (name, decl, class_binding_level); ok = true; } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, ok); } /* Process "using SCOPE::NAME" in a class scope. Return the USING_DECL created. */ tree do_class_using_decl (tree scope, tree name) { /* The USING_DECL returned by this function. */ tree value; /* The declaration (or declarations) name by this using declaration. NULL if we are in a template and cannot figure out what has been named. */ tree decl; /* True if SCOPE is a dependent type. */ bool scope_dependent_p; /* True if SCOPE::NAME is dependent. */ bool name_dependent_p; /* True if any of the bases of CURRENT_CLASS_TYPE are dependent. */ bool bases_dependent_p; tree binfo; tree base_binfo; int i; if (name == error_mark_node) return NULL_TREE; if (!scope || !TYPE_P (scope)) { error ("using-declaration for non-member at class scope"); return NULL_TREE; } /* Make sure the name is not invalid */ if (TREE_CODE (name) == BIT_NOT_EXPR) { error ("%<%T::%D%> names destructor", scope, name); return NULL_TREE; } if (constructor_name_p (name, scope)) { error ("%<%T::%D%> names constructor", scope, name); return NULL_TREE; } if (constructor_name_p (name, current_class_type)) { error ("%<%T::%D%> names constructor in %qT", scope, name, current_class_type); return NULL_TREE; } scope_dependent_p = dependent_type_p (scope); name_dependent_p = (scope_dependent_p || (IDENTIFIER_TYPENAME_P (name) && dependent_type_p (TREE_TYPE (name)))); bases_dependent_p = false; if (processing_template_decl) for (binfo = TYPE_BINFO (current_class_type), i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) if (dependent_type_p (TREE_TYPE (base_binfo))) { bases_dependent_p = true; break; } decl = NULL_TREE; /* From [namespace.udecl]: A using-declaration used as a member-declaration shall refer to a member of a base class of the class being defined. In general, we cannot check this constraint in a template because we do not know the entire set of base classes of the current class type. However, if all of the base classes are non-dependent, then we can avoid delaying the check until instantiation. */ if (!scope_dependent_p) { base_kind b_kind; binfo = lookup_base (current_class_type, scope, ba_any, &b_kind); if (b_kind < bk_proper_base) { if (!bases_dependent_p) { error_not_base_type (scope, current_class_type); return NULL_TREE; } } else if (!name_dependent_p) { decl = lookup_member (binfo, name, 0, false); if (!decl) { error ("no members matching %<%T::%D%> in %q#T", scope, name, scope); return NULL_TREE; } /* The binfo from which the functions came does not matter. */ if (BASELINK_P (decl)) decl = BASELINK_FUNCTIONS (decl); } } value = build_lang_decl (USING_DECL, name, NULL_TREE); USING_DECL_DECLS (value) = decl; USING_DECL_SCOPE (value) = scope; DECL_DEPENDENT_P (value) = !decl; return value; } /* Return the binding value for name in scope. */ tree namespace_binding (tree name, tree scope) { cxx_binding *binding; if (scope == NULL) scope = global_namespace; else /* Unnecessary for the global namespace because it can't be an alias. */ scope = ORIGINAL_NAMESPACE (scope); binding = cxx_scope_find_binding_for_name (NAMESPACE_LEVEL (scope), name); return binding ? binding->value : NULL_TREE; } /* Set the binding value for name in scope. */ void set_namespace_binding (tree name, tree scope, tree val) { cxx_binding *b; timevar_push (TV_NAME_LOOKUP); if (scope == NULL_TREE) scope = global_namespace; b = binding_for_name (NAMESPACE_LEVEL (scope), name); if (!b->value || TREE_CODE (val) == OVERLOAD || val == error_mark_node) b->value = val; else supplement_binding (b, val); timevar_pop (TV_NAME_LOOKUP); } /* Set the context of a declaration to scope. Complain if we are not outside scope. */ void set_decl_namespace (tree decl, tree scope, bool friendp) { tree old, fn; /* Get rid of namespace aliases. */ scope = ORIGINAL_NAMESPACE (scope); /* It is ok for friends to be qualified in parallel space. */ if (!friendp && !is_ancestor (current_namespace, scope)) error ("declaration of %qD not in a namespace surrounding %qD", decl, scope); DECL_CONTEXT (decl) = FROB_CONTEXT (scope); /* Writing "int N::i" to declare a variable within "N" is invalid. */ if (scope == current_namespace) { if (at_namespace_scope_p ()) error ("explicit qualification in declaration of %qD", decl); return; } /* See whether this has been declared in the namespace. */ old = lookup_qualified_name (scope, DECL_NAME (decl), false, true); if (old == error_mark_node) /* No old declaration at all. */ goto complain; if (!is_overloaded_fn (decl)) /* Don't compare non-function decls with decls_match here, since it can't check for the correct constness at this point. pushdecl will find those errors later. */ return; /* Since decl is a function, old should contain a function decl. */ if (!is_overloaded_fn (old)) goto complain; fn = OVL_CURRENT (old); if (!is_associated_namespace (scope, CP_DECL_CONTEXT (fn))) goto complain; /* A template can be explicitly specialized in any namespace. */ if (processing_explicit_instantiation) return; if (processing_template_decl || processing_specialization) /* We have not yet called push_template_decl to turn a FUNCTION_DECL into a TEMPLATE_DECL, so the declarations won't match. But, we'll check later, when we construct the template. */ return; /* Instantiations or specializations of templates may be declared as friends in any namespace. */ if (friendp && DECL_USE_TEMPLATE (decl)) return; if (is_overloaded_fn (old)) { for (; old; old = OVL_NEXT (old)) if (decls_match (decl, OVL_CURRENT (old))) return; } else if (decls_match (decl, old)) return; complain: error ("%qD should have been declared inside %qD", decl, scope); } /* Return the namespace where the current declaration is declared. */ static tree current_decl_namespace (void) { tree result; /* If we have been pushed into a different namespace, use it. */ if (decl_namespace_list) return TREE_PURPOSE (decl_namespace_list); if (current_class_type) result = decl_namespace_context (current_class_type); else if (current_function_decl) result = decl_namespace_context (current_function_decl); else result = current_namespace; return result; } /* Process any ATTRIBUTES on a namespace definition. Currently only attribute visibility is meaningful, which is a property of the syntactic block rather than the namespace as a whole, so we don't touch the NAMESPACE_DECL at all. Returns true if attribute visibility is seen. */ bool handle_namespace_attrs (tree ns, tree attributes) { tree d; bool saw_vis = false; for (d = attributes; d; d = TREE_CHAIN (d)) { tree name = TREE_PURPOSE (d); tree args = TREE_VALUE (d); #ifdef HANDLE_PRAGMA_VISIBILITY if (is_attribute_p ("visibility", name)) { tree x = args ? TREE_VALUE (args) : NULL_TREE; if (x == NULL_TREE || TREE_CODE (x) != STRING_CST || TREE_CHAIN (args)) { warning (OPT_Wattributes, "%qD attribute requires a single NTBS argument", name); continue; } if (!TREE_PUBLIC (ns)) warning (OPT_Wattributes, "%qD attribute is meaningless since members of the " "anonymous namespace get local symbols", name); push_visibility (TREE_STRING_POINTER (x)); saw_vis = true; } else #endif { warning (OPT_Wattributes, "%qD attribute directive ignored", name); continue; } } return saw_vis; } /* Push into the scope of the NAME namespace. If NAME is NULL_TREE, then we select a name that is unique to this compilation unit. */ void push_namespace (tree name) { tree d = NULL_TREE; int need_new = 1; int implicit_use = 0; bool anon = !name; timevar_push (TV_NAME_LOOKUP); /* We should not get here if the global_namespace is not yet constructed nor if NAME designates the global namespace: The global scope is constructed elsewhere. */ gcc_assert (global_namespace != NULL && name != global_scope_name); if (anon) { name = get_anonymous_namespace_name(); d = IDENTIFIER_NAMESPACE_VALUE (name); if (d) /* Reopening anonymous namespace. */ need_new = 0; implicit_use = 1; } else { /* Check whether this is an extended namespace definition. */ d = IDENTIFIER_NAMESPACE_VALUE (name); if (d != NULL_TREE && TREE_CODE (d) == NAMESPACE_DECL) { need_new = 0; if (DECL_NAMESPACE_ALIAS (d)) { error ("namespace alias %qD not allowed here, assuming %qD", d, DECL_NAMESPACE_ALIAS (d)); d = DECL_NAMESPACE_ALIAS (d); } } } if (need_new) { /* Make a new namespace, binding the name to it. */ d = build_lang_decl (NAMESPACE_DECL, name, void_type_node); DECL_CONTEXT (d) = FROB_CONTEXT (current_namespace); /* The name of this namespace is not visible to other translation units if it is an anonymous namespace or member thereof. */ if (anon || decl_anon_ns_mem_p (current_namespace)) TREE_PUBLIC (d) = 0; else TREE_PUBLIC (d) = 1; pushdecl (d); if (anon) { /* Clear DECL_NAME for the benefit of debugging back ends. */ SET_DECL_ASSEMBLER_NAME (d, name); DECL_NAME (d) = NULL_TREE; } begin_scope (sk_namespace, d); } else resume_scope (NAMESPACE_LEVEL (d)); if (implicit_use) do_using_directive (d); /* Enter the name space. */ current_namespace = d; timevar_pop (TV_NAME_LOOKUP); } /* Pop from the scope of the current namespace. */ void pop_namespace (void) { gcc_assert (current_namespace != global_namespace); current_namespace = CP_DECL_CONTEXT (current_namespace); /* The binding level is not popped, as it might be re-opened later. */ leave_scope (); } /* Push into the scope of the namespace NS, even if it is deeply nested within another namespace. */ void push_nested_namespace (tree ns) { if (ns == global_namespace) push_to_top_level (); else { push_nested_namespace (CP_DECL_CONTEXT (ns)); push_namespace (DECL_NAME (ns)); } } /* Pop back from the scope of the namespace NS, which was previously entered with push_nested_namespace. */ void pop_nested_namespace (tree ns) { timevar_push (TV_NAME_LOOKUP); while (ns != global_namespace) { pop_namespace (); ns = CP_DECL_CONTEXT (ns); } pop_from_top_level (); timevar_pop (TV_NAME_LOOKUP); } /* Temporarily set the namespace for the current declaration. */ void push_decl_namespace (tree decl) { if (TREE_CODE (decl) != NAMESPACE_DECL) decl = decl_namespace_context (decl); decl_namespace_list = tree_cons (ORIGINAL_NAMESPACE (decl), NULL_TREE, decl_namespace_list); } /* [namespace.memdef]/2 */ void pop_decl_namespace (void) { decl_namespace_list = TREE_CHAIN (decl_namespace_list); } /* Return the namespace that is the common ancestor of two given namespaces. */ static tree namespace_ancestor (tree ns1, tree ns2) { timevar_push (TV_NAME_LOOKUP); if (is_ancestor (ns1, ns2)) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, ns1); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, namespace_ancestor (CP_DECL_CONTEXT (ns1), ns2)); } /* Process a namespace-alias declaration. */ void do_namespace_alias (tree alias, tree namespace) { if (namespace == error_mark_node) return; gcc_assert (TREE_CODE (namespace) == NAMESPACE_DECL); namespace = ORIGINAL_NAMESPACE (namespace); /* Build the alias. */ alias = build_lang_decl (NAMESPACE_DECL, alias, void_type_node); DECL_NAMESPACE_ALIAS (alias) = namespace; DECL_EXTERNAL (alias) = 1; DECL_CONTEXT (alias) = FROB_CONTEXT (current_scope ()); pushdecl (alias); /* Emit debug info for namespace alias. */ (*debug_hooks->global_decl) (alias); } /* Like pushdecl, only it places X in the current namespace, if appropriate. */ tree pushdecl_namespace_level (tree x, bool is_friend) { struct cp_binding_level *b = current_binding_level; tree t; timevar_push (TV_NAME_LOOKUP); t = pushdecl_with_scope (x, NAMESPACE_LEVEL (current_namespace), is_friend); /* Now, the type_shadowed stack may screw us. Munge it so it does what we want. */ if (TREE_CODE (t) == TYPE_DECL) { tree name = DECL_NAME (t); tree newval; tree *ptr = (tree *)0; for (; !global_scope_p (b); b = b->level_chain) { tree shadowed = b->type_shadowed; for (; shadowed; shadowed = TREE_CHAIN (shadowed)) if (TREE_PURPOSE (shadowed) == name) { ptr = &TREE_VALUE (shadowed); /* Can't break out of the loop here because sometimes a binding level will have duplicate bindings for PT names. It's gross, but I haven't time to fix it. */ } } newval = TREE_TYPE (t); if (ptr == (tree *)0) { /* @@ This shouldn't be needed. My test case "zstring.cc" trips up here if this is changed to an assertion. --KR */ SET_IDENTIFIER_TYPE_VALUE (name, t); } else { *ptr = newval; } } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } /* Insert USED into the using list of USER. Set INDIRECT_flag if this directive is not directly from the source. Also find the common ancestor and let our users know about the new namespace */ static void add_using_namespace (tree user, tree used, bool indirect) { tree t; timevar_push (TV_NAME_LOOKUP); /* Using oneself is a no-op. */ if (user == used) { timevar_pop (TV_NAME_LOOKUP); return; } gcc_assert (TREE_CODE (user) == NAMESPACE_DECL); gcc_assert (TREE_CODE (used) == NAMESPACE_DECL); /* Check if we already have this. */ t = purpose_member (used, DECL_NAMESPACE_USING (user)); if (t != NULL_TREE) { if (!indirect) /* Promote to direct usage. */ TREE_INDIRECT_USING (t) = 0; timevar_pop (TV_NAME_LOOKUP); return; } /* Add used to the user's using list. */ DECL_NAMESPACE_USING (user) = tree_cons (used, namespace_ancestor (user, used), DECL_NAMESPACE_USING (user)); TREE_INDIRECT_USING (DECL_NAMESPACE_USING (user)) = indirect; /* Add user to the used's users list. */ DECL_NAMESPACE_USERS (used) = tree_cons (user, 0, DECL_NAMESPACE_USERS (used)); /* Recursively add all namespaces used. */ for (t = DECL_NAMESPACE_USING (used); t; t = TREE_CHAIN (t)) /* indirect usage */ add_using_namespace (user, TREE_PURPOSE (t), 1); /* Tell everyone using us about the new used namespaces. */ for (t = DECL_NAMESPACE_USERS (user); t; t = TREE_CHAIN (t)) add_using_namespace (TREE_PURPOSE (t), used, 1); timevar_pop (TV_NAME_LOOKUP); } /* Process a using-declaration not appearing in class or local scope. */ void do_toplevel_using_decl (tree decl, tree scope, tree name) { tree oldval, oldtype, newval, newtype; tree orig_decl = decl; cxx_binding *binding; decl = validate_nonmember_using_decl (decl, scope, name); if (decl == NULL_TREE) return; binding = binding_for_name (NAMESPACE_LEVEL (current_namespace), name); oldval = binding->value; oldtype = binding->type; do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype); /* Emit debug info. */ if (!processing_template_decl) cp_emit_debug_info_for_using (orig_decl, current_namespace); /* Copy declarations found. */ if (newval) binding->value = newval; if (newtype) binding->type = newtype; } /* Process a using-directive. */ void do_using_directive (tree namespace) { tree context = NULL_TREE; if (namespace == error_mark_node) return; gcc_assert (TREE_CODE (namespace) == NAMESPACE_DECL); if (building_stmt_tree ()) add_stmt (build_stmt (USING_STMT, namespace)); namespace = ORIGINAL_NAMESPACE (namespace); if (!toplevel_bindings_p ()) { push_using_directive (namespace); context = current_scope (); } else { /* direct usage */ add_using_namespace (current_namespace, namespace, 0); if (current_namespace != global_namespace) context = current_namespace; } /* Emit debugging info. */ if (!processing_template_decl) (*debug_hooks->imported_module_or_decl) (namespace, context); } /* Deal with a using-directive seen by the parser. Currently we only handle attributes here, since they cannot appear inside a template. */ void parse_using_directive (tree namespace, tree attribs) { tree a; do_using_directive (namespace); for (a = attribs; a; a = TREE_CHAIN (a)) { tree name = TREE_PURPOSE (a); if (is_attribute_p ("strong", name)) { if (!toplevel_bindings_p ()) error ("strong using only meaningful at namespace scope"); else if (namespace != error_mark_node) { if (!is_ancestor (current_namespace, namespace)) error ("current namespace %qD does not enclose strongly used namespace %qD", current_namespace, namespace); DECL_NAMESPACE_ASSOCIATIONS (namespace) = tree_cons (current_namespace, 0, DECL_NAMESPACE_ASSOCIATIONS (namespace)); } } else warning (OPT_Wattributes, "%qD attribute directive ignored", name); } } /* Like pushdecl, only it places X in the global scope if appropriate. Calls cp_finish_decl to register the variable, initializing it with *INIT, if INIT is non-NULL. */ static tree pushdecl_top_level_1 (tree x, tree *init, bool is_friend) { timevar_push (TV_NAME_LOOKUP); push_to_top_level (); x = pushdecl_namespace_level (x, is_friend); if (init) finish_decl (x, *init, NULL_TREE); pop_from_top_level (); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, x); } /* Like pushdecl, only it places X in the global scope if appropriate. */ tree pushdecl_top_level (tree x) { return pushdecl_top_level_1 (x, NULL, false); } /* Like pushdecl_top_level, but adding the IS_FRIEND parameter. */ tree pushdecl_top_level_maybe_friend (tree x, bool is_friend) { return pushdecl_top_level_1 (x, NULL, is_friend); } /* Like pushdecl, only it places X in the global scope if appropriate. Calls cp_finish_decl to register the variable, initializing it with INIT. */ tree pushdecl_top_level_and_finish (tree x, tree init) { return pushdecl_top_level_1 (x, &init, false); } /* Combines two sets of overloaded functions into an OVERLOAD chain, removing duplicates. The first list becomes the tail of the result. The algorithm is O(n^2). We could get this down to O(n log n) by doing a sort on the addresses of the functions, if that becomes necessary. */ static tree merge_functions (tree s1, tree s2) { for (; s2; s2 = OVL_NEXT (s2)) { tree fn2 = OVL_CURRENT (s2); tree fns1; for (fns1 = s1; fns1; fns1 = OVL_NEXT (fns1)) { tree fn1 = OVL_CURRENT (fns1); /* If the function from S2 is already in S1, there is no need to add it again. For `extern "C"' functions, we might have two FUNCTION_DECLs for the same function, in different namespaces; again, we only need one of them. */ if (fn1 == fn2 || (DECL_EXTERN_C_P (fn1) && DECL_EXTERN_C_P (fn2) && DECL_NAME (fn1) == DECL_NAME (fn2))) break; } /* If we exhausted all of the functions in S1, FN2 is new. */ if (!fns1) s1 = build_overload (fn2, s1); } return s1; } /* This should return an error not all definitions define functions. It is not an error if we find two functions with exactly the same signature, only if these are selected in overload resolution. old is the current set of bindings, new the freshly-found binding. XXX Do we want to give *all* candidates in case of ambiguity? XXX In what way should I treat extern declarations? XXX I don't want to repeat the entire duplicate_decls here */ static void ambiguous_decl (struct scope_binding *old, cxx_binding *new, int flags) { tree val, type; gcc_assert (old != NULL); /* Copy the type. */ type = new->type; if (LOOKUP_NAMESPACES_ONLY (flags) || (type && hidden_name_p (type) && !(flags & LOOKUP_HIDDEN))) type = NULL_TREE; /* Copy the value. */ val = new->value; if (val) { if (hidden_name_p (val) && !(flags & LOOKUP_HIDDEN)) val = NULL_TREE; else switch (TREE_CODE (val)) { case TEMPLATE_DECL: /* If we expect types or namespaces, and not templates, or this is not a template class. */ if ((LOOKUP_QUALIFIERS_ONLY (flags) && !DECL_CLASS_TEMPLATE_P (val))) val = NULL_TREE; break; case TYPE_DECL: if (LOOKUP_NAMESPACES_ONLY (flags) || (type && (flags & LOOKUP_PREFER_TYPES))) val = NULL_TREE; break; case NAMESPACE_DECL: if (LOOKUP_TYPES_ONLY (flags)) val = NULL_TREE; break; case FUNCTION_DECL: /* Ignore built-in functions that are still anticipated. */ if (LOOKUP_QUALIFIERS_ONLY (flags)) val = NULL_TREE; break; default: if (LOOKUP_QUALIFIERS_ONLY (flags)) val = NULL_TREE; } } /* If val is hidden, shift down any class or enumeration name. */ if (!val) { val = type; type = NULL_TREE; } if (!old->value) old->value = val; else if (val && val != old->value) { if (is_overloaded_fn (old->value) && is_overloaded_fn (val)) old->value = merge_functions (old->value, val); else { old->value = tree_cons (NULL_TREE, old->value, build_tree_list (NULL_TREE, val)); TREE_TYPE (old->value) = error_mark_node; } } if (!old->type) old->type = type; else if (type && old->type != type) { old->type = tree_cons (NULL_TREE, old->type, build_tree_list (NULL_TREE, type)); TREE_TYPE (old->type) = error_mark_node; } } /* Return the declarations that are members of the namespace NS. */ tree cp_namespace_decls (tree ns) { return NAMESPACE_LEVEL (ns)->names; } /* Combine prefer_type and namespaces_only into flags. */ static int lookup_flags (int prefer_type, int namespaces_only) { if (namespaces_only) return LOOKUP_PREFER_NAMESPACES; if (prefer_type > 1) return LOOKUP_PREFER_TYPES; if (prefer_type > 0) return LOOKUP_PREFER_BOTH; return 0; } /* Given a lookup that returned VAL, use FLAGS to decide if we want to ignore it or not. Subroutine of lookup_name_real and lookup_type_scope. */ static bool qualify_lookup (tree val, int flags) { if (val == NULL_TREE) return false; if ((flags & LOOKUP_PREFER_NAMESPACES) && TREE_CODE (val) == NAMESPACE_DECL) return true; if ((flags & LOOKUP_PREFER_TYPES) && (TREE_CODE (val) == TYPE_DECL || TREE_CODE (val) == TEMPLATE_DECL)) return true; if (flags & (LOOKUP_PREFER_NAMESPACES | LOOKUP_PREFER_TYPES)) return false; return true; } /* Given a lookup that returned VAL, decide if we want to ignore it or not based on DECL_ANTICIPATED. */ bool hidden_name_p (tree val) { if (DECL_P (val) && DECL_LANG_SPECIFIC (val) && DECL_ANTICIPATED (val)) return true; return false; } /* Remove any hidden friend functions from a possibly overloaded set of functions. */ tree remove_hidden_names (tree fns) { if (!fns) return fns; if (TREE_CODE (fns) == FUNCTION_DECL && hidden_name_p (fns)) fns = NULL_TREE; else if (TREE_CODE (fns) == OVERLOAD) { tree o; for (o = fns; o; o = OVL_NEXT (o)) if (hidden_name_p (OVL_CURRENT (o))) break; if (o) { tree n = NULL_TREE; for (o = fns; o; o = OVL_NEXT (o)) if (!hidden_name_p (OVL_CURRENT (o))) n = build_overload (OVL_CURRENT (o), n); fns = n; } } return fns; } /* Unscoped lookup of a global: iterate over current namespaces, considering using-directives. */ static tree unqualified_namespace_lookup (tree name, int flags) { tree initial = current_decl_namespace (); tree scope = initial; tree siter; struct cp_binding_level *level; tree val = NULL_TREE; timevar_push (TV_NAME_LOOKUP); for (; !val; scope = CP_DECL_CONTEXT (scope)) { struct scope_binding binding = EMPTY_SCOPE_BINDING; cxx_binding *b = cxx_scope_find_binding_for_name (NAMESPACE_LEVEL (scope), name); if (b) ambiguous_decl (&binding, b, flags); /* Add all _DECLs seen through local using-directives. */ for (level = current_binding_level; level->kind != sk_namespace; level = level->level_chain) if (!lookup_using_namespace (name, &binding, level->using_directives, scope, flags)) /* Give up because of error. */ POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node); /* Add all _DECLs seen through global using-directives. */ /* XXX local and global using lists should work equally. */ siter = initial; while (1) { if (!lookup_using_namespace (name, &binding, DECL_NAMESPACE_USING (siter), scope, flags)) /* Give up because of error. */ POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node); if (siter == scope) break; siter = CP_DECL_CONTEXT (siter); } val = binding.value; if (scope == global_namespace) break; } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, val); } /* Look up NAME (an IDENTIFIER_NODE) in SCOPE (either a NAMESPACE_DECL or a class TYPE). If IS_TYPE_P is TRUE, then ignore non-type bindings. Returns a DECL (or OVERLOAD, or BASELINK) representing the declaration found. If no suitable declaration can be found, ERROR_MARK_NODE is returned. If COMPLAIN is true and SCOPE is neither a class-type nor a namespace a diagnostic is issued. */ tree lookup_qualified_name (tree scope, tree name, bool is_type_p, bool complain) { int flags = 0; tree t = NULL_TREE; if (TREE_CODE (scope) == NAMESPACE_DECL) { struct scope_binding binding = EMPTY_SCOPE_BINDING; flags |= LOOKUP_COMPLAIN; if (is_type_p) flags |= LOOKUP_PREFER_TYPES; if (qualified_lookup_using_namespace (name, scope, &binding, flags)) t = binding.value; } else if (is_aggr_type (scope, complain)) t = lookup_member (scope, name, 2, is_type_p); if (!t) return error_mark_node; return t; } /* Subroutine of unqualified_namespace_lookup: Add the bindings of NAME in used namespaces to VAL. We are currently looking for names in namespace SCOPE, so we look through USINGS for using-directives of namespaces which have SCOPE as a common ancestor with the current scope. Returns false on errors. */ static bool lookup_using_namespace (tree name, struct scope_binding *val, tree usings, tree scope, int flags) { tree iter; timevar_push (TV_NAME_LOOKUP); /* Iterate over all used namespaces in current, searching for using directives of scope. */ for (iter = usings; iter; iter = TREE_CHAIN (iter)) if (TREE_VALUE (iter) == scope) { tree used = ORIGINAL_NAMESPACE (TREE_PURPOSE (iter)); cxx_binding *val1 = cxx_scope_find_binding_for_name (NAMESPACE_LEVEL (used), name); /* Resolve ambiguities. */ if (val1) ambiguous_decl (val, val1, flags); } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, val->value != error_mark_node); } /* [namespace.qual] Accepts the NAME to lookup and its qualifying SCOPE. Returns the name/type pair found into the cxx_binding *RESULT, or false on error. */ static bool qualified_lookup_using_namespace (tree name, tree scope, struct scope_binding *result, int flags) { /* Maintain a list of namespaces visited... */ tree seen = NULL_TREE; /* ... and a list of namespace yet to see. */ tree todo = NULL_TREE; tree todo_maybe = NULL_TREE; tree usings; timevar_push (TV_NAME_LOOKUP); /* Look through namespace aliases. */ scope = ORIGINAL_NAMESPACE (scope); while (scope && result->value != error_mark_node) { cxx_binding *binding = cxx_scope_find_binding_for_name (NAMESPACE_LEVEL (scope), name); seen = tree_cons (scope, NULL_TREE, seen); if (binding) ambiguous_decl (result, binding, flags); /* Consider strong using directives always, and non-strong ones if we haven't found a binding yet. ??? Shouldn't we consider non-strong ones if the initial RESULT is non-NULL, but the binding in the given namespace is? */ for (usings = DECL_NAMESPACE_USING (scope); usings; usings = TREE_CHAIN (usings)) /* If this was a real directive, and we have not seen it. */ if (!TREE_INDIRECT_USING (usings)) { /* Try to avoid queuing the same namespace more than once, the exception being when a namespace was already enqueued for todo_maybe and then a strong using is found for it. We could try to remove it from todo_maybe, but it's probably not worth the effort. */ if (is_associated_namespace (scope, TREE_PURPOSE (usings)) && !purpose_member (TREE_PURPOSE (usings), seen) && !purpose_member (TREE_PURPOSE (usings), todo)) todo = tree_cons (TREE_PURPOSE (usings), NULL_TREE, todo); else if ((!result->value && !result->type) && !purpose_member (TREE_PURPOSE (usings), seen) && !purpose_member (TREE_PURPOSE (usings), todo) && !purpose_member (TREE_PURPOSE (usings), todo_maybe)) todo_maybe = tree_cons (TREE_PURPOSE (usings), NULL_TREE, todo_maybe); } if (todo) { scope = TREE_PURPOSE (todo); todo = TREE_CHAIN (todo); } else if (todo_maybe && (!result->value && !result->type)) { scope = TREE_PURPOSE (todo_maybe); todo = TREE_CHAIN (todo_maybe); todo_maybe = NULL_TREE; } else scope = NULL_TREE; /* If there never was a todo list. */ } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, result->value != error_mark_node); } /* Return the innermost non-namespace binding for NAME from a scope containing BINDING, or, if BINDING is NULL, the current scope. If CLASS_P is false, then class bindings are ignored. */ cxx_binding * outer_binding (tree name, cxx_binding *binding, bool class_p) { cxx_binding *outer; cxx_scope *scope; cxx_scope *outer_scope; if (binding) { scope = binding->scope->level_chain; outer = binding->previous; } else { scope = current_binding_level; outer = IDENTIFIER_BINDING (name); } outer_scope = outer ? outer->scope : NULL; /* Because we create class bindings lazily, we might be missing a class binding for NAME. If there are any class binding levels between the LAST_BINDING_LEVEL and the scope in which OUTER was declared, we must lookup NAME in those class scopes. */ if (class_p) while (scope && scope != outer_scope && scope->kind != sk_namespace) { if (scope->kind == sk_class) { cxx_binding *class_binding; class_binding = get_class_binding (name, scope); if (class_binding) { /* Thread this new class-scope binding onto the IDENTIFIER_BINDING list so that future lookups find it quickly. */ class_binding->previous = outer; if (binding) binding->previous = class_binding; else IDENTIFIER_BINDING (name) = class_binding; return class_binding; } } scope = scope->level_chain; } return outer; } /* Return the innermost block-scope or class-scope value binding for NAME, or NULL_TREE if there is no such binding. */ tree innermost_non_namespace_value (tree name) { cxx_binding *binding; binding = outer_binding (name, /*binding=*/NULL, /*class_p=*/true); return binding ? binding->value : NULL_TREE; } /* Look up NAME in the current binding level and its superiors in the namespace of variables, functions and typedefs. Return a ..._DECL node of some kind representing its definition if there is only one such declaration, or return a TREE_LIST with all the overloaded definitions if there are many, or return 0 if it is undefined. Hidden name, either friend declaration or built-in function, are not ignored. If PREFER_TYPE is > 0, we prefer TYPE_DECLs or namespaces. If PREFER_TYPE is > 1, we reject non-type decls (e.g. namespaces). Otherwise we prefer non-TYPE_DECLs. If NONCLASS is nonzero, bindings in class scopes are ignored. If BLOCK_P is false, bindings in block scopes are ignored. */ tree lookup_name_real (tree name, int prefer_type, int nonclass, bool block_p, int namespaces_only, int flags) { cxx_binding *iter; tree val = NULL_TREE; timevar_push (TV_NAME_LOOKUP); /* Conversion operators are handled specially because ordinary unqualified name lookup will not find template conversion operators. */ if (IDENTIFIER_TYPENAME_P (name)) { struct cp_binding_level *level; for (level = current_binding_level; level && level->kind != sk_namespace; level = level->level_chain) { tree class_type; tree operators; /* A conversion operator can only be declared in a class scope. */ if (level->kind != sk_class) continue; /* Lookup the conversion operator in the class. */ class_type = level->this_entity; operators = lookup_fnfields (class_type, name, /*protect=*/0); if (operators) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, operators); } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, NULL_TREE); } flags |= lookup_flags (prefer_type, namespaces_only); /* First, look in non-namespace scopes. */ if (current_class_type == NULL_TREE) nonclass = 1; if (block_p || !nonclass) for (iter = outer_binding (name, NULL, !nonclass); iter; iter = outer_binding (name, iter, !nonclass)) { tree binding; /* Skip entities we don't want. */ if (LOCAL_BINDING_P (iter) ? !block_p : nonclass) continue; /* If this is the kind of thing we're looking for, we're done. */ if (qualify_lookup (iter->value, flags)) binding = iter->value; else if ((flags & LOOKUP_PREFER_TYPES) && qualify_lookup (iter->type, flags)) binding = iter->type; else binding = NULL_TREE; if (binding) { if (hidden_name_p (binding)) { /* A non namespace-scope binding can only be hidden if we are in a local class, due to friend declarations. In particular, consider: void f() { struct A { friend struct B; void g() { B* b; } // error: B is hidden } struct B {}; } The standard says that "B" is a local class in "f" (but not nested within "A") -- but that name lookup for "B" does not find this declaration until it is declared directly with "f". In particular: [class.friend] If a friend declaration appears in a local class and the name specified is an unqualified name, a prior declaration is looked up without considering scopes that are outside the innermost enclosing non-class scope. For a friend class declaration, if there is no prior declaration, the class that is specified belongs to the innermost enclosing non-class scope, but if it is subsequently referenced, its name is not found by name lookup until a matching declaration is provided in the innermost enclosing nonclass scope. */ gcc_assert (current_class_type && LOCAL_CLASS_P (current_class_type)); /* This binding comes from a friend declaration in the local class. The standard (11.4.8) states that the lookup can only succeed if there is a non-hidden declaration in the current scope, which is not the case here. */ POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, NULL_TREE); } val = binding; break; } } /* Now lookup in namespace scopes. */ if (!val) val = unqualified_namespace_lookup (name, flags); /* If we have a single function from a using decl, pull it out. */ if (val && TREE_CODE (val) == OVERLOAD && !really_overloaded_fn (val)) val = OVL_FUNCTION (val); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, val); } tree lookup_name_nonclass (tree name) { return lookup_name_real (name, 0, 1, /*block_p=*/true, 0, LOOKUP_COMPLAIN); } tree lookup_function_nonclass (tree name, tree args, bool block_p) { return lookup_arg_dependent (name, lookup_name_real (name, 0, 1, block_p, 0, LOOKUP_COMPLAIN), args); } tree lookup_name (tree name) { return lookup_name_real (name, 0, 0, /*block_p=*/true, 0, LOOKUP_COMPLAIN); } tree lookup_name_prefer_type (tree name, int prefer_type) { return lookup_name_real (name, prefer_type, 0, /*block_p=*/true, 0, LOOKUP_COMPLAIN); } /* Look up NAME for type used in elaborated name specifier in the scopes given by SCOPE. SCOPE can be either TS_CURRENT or TS_WITHIN_ENCLOSING_NON_CLASS. Although not implied by the name, more scopes are checked if cleanup or template parameter scope is encountered. Unlike lookup_name_real, we make sure that NAME is actually declared in the desired scope, not from inheritance, nor using directive. For using declaration, there is DR138 still waiting to be resolved. Hidden name coming from an earlier friend declaration is also returned. A TYPE_DECL best matching the NAME is returned. Catching error and issuing diagnostics are caller's responsibility. */ tree lookup_type_scope (tree name, tag_scope scope) { cxx_binding *iter = NULL; tree val = NULL_TREE; timevar_push (TV_NAME_LOOKUP); /* Look in non-namespace scope first. */ if (current_binding_level->kind != sk_namespace) iter = outer_binding (name, NULL, /*class_p=*/ true); for (; iter; iter = outer_binding (name, iter, /*class_p=*/ true)) { /* Check if this is the kind of thing we're looking for. If SCOPE is TS_CURRENT, also make sure it doesn't come from base class. For ITER->VALUE, we can simply use INHERITED_VALUE_BINDING_P. For ITER->TYPE, we have to use our own check. We check ITER->TYPE before ITER->VALUE in order to handle typedef struct C {} C; correctly. */ if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES) && (scope != ts_current || LOCAL_BINDING_P (iter) || DECL_CONTEXT (iter->type) == iter->scope->this_entity)) val = iter->type; else if ((scope != ts_current || !INHERITED_VALUE_BINDING_P (iter)) && qualify_lookup (iter->value, LOOKUP_PREFER_TYPES)) val = iter->value; if (val) break; } /* Look in namespace scope. */ if (!val) { iter = cxx_scope_find_binding_for_name (NAMESPACE_LEVEL (current_decl_namespace ()), name); if (iter) { /* If this is the kind of thing we're looking for, we're done. */ if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES)) val = iter->type; else if (qualify_lookup (iter->value, LOOKUP_PREFER_TYPES)) val = iter->value; } } /* Type found, check if it is in the allowed scopes, ignoring cleanup and template parameter scopes. */ if (val) { struct cp_binding_level *b = current_binding_level; while (b) { if (iter->scope == b) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, val); if (b->kind == sk_cleanup || b->kind == sk_template_parms) b = b->level_chain; else if (b->kind == sk_class && scope == ts_within_enclosing_non_class) b = b->level_chain; else break; } } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, NULL_TREE); } /* Similar to `lookup_name' but look only in the innermost non-class binding level. */ static tree lookup_name_innermost_nonclass_level (tree name) { struct cp_binding_level *b; tree t = NULL_TREE; timevar_push (TV_NAME_LOOKUP); b = innermost_nonclass_level (); if (b->kind == sk_namespace) { t = IDENTIFIER_NAMESPACE_VALUE (name); /* extern "C" function() */ if (t != NULL_TREE && TREE_CODE (t) == TREE_LIST) t = TREE_VALUE (t); } else if (IDENTIFIER_BINDING (name) && LOCAL_BINDING_P (IDENTIFIER_BINDING (name))) { cxx_binding *binding; binding = IDENTIFIER_BINDING (name); while (1) { if (binding->scope == b && !(TREE_CODE (binding->value) == VAR_DECL && DECL_DEAD_FOR_LOCAL (binding->value))) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, binding->value); if (b->kind == sk_cleanup) b = b->level_chain; else break; } } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } /* Like lookup_name_innermost_nonclass_level, but for types. */ static tree lookup_type_current_level (tree name) { tree t = NULL_TREE; timevar_push (TV_NAME_LOOKUP); gcc_assert (current_binding_level->kind != sk_namespace); if (REAL_IDENTIFIER_TYPE_VALUE (name) != NULL_TREE && REAL_IDENTIFIER_TYPE_VALUE (name) != global_type_node) { struct cp_binding_level *b = current_binding_level; while (1) { if (purpose_member (name, b->type_shadowed)) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, REAL_IDENTIFIER_TYPE_VALUE (name)); if (b->kind == sk_cleanup) b = b->level_chain; else break; } } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t); } /* [basic.lookup.koenig] */ /* A nonzero return value in the functions below indicates an error. */ struct arg_lookup { tree name; tree args; tree namespaces; tree classes; tree functions; }; static bool arg_assoc (struct arg_lookup*, tree); static bool arg_assoc_args (struct arg_lookup*, tree); static bool arg_assoc_type (struct arg_lookup*, tree); static bool add_function (struct arg_lookup *, tree); static bool arg_assoc_namespace (struct arg_lookup *, tree); static bool arg_assoc_class (struct arg_lookup *, tree); static bool arg_assoc_template_arg (struct arg_lookup*, tree); /* Add a function to the lookup structure. Returns true on error. */ static bool add_function (struct arg_lookup *k, tree fn) { /* We used to check here to see if the function was already in the list, but that's O(n^2), which is just too expensive for function lookup. Now we deal with the occasional duplicate in joust. In doing this, we assume that the number of duplicates will be small compared to the total number of functions being compared, which should usually be the case. */ /* We must find only functions, or exactly one non-function. */ if (!k->functions) k->functions = fn; else if (fn == k->functions) ; else if (is_overloaded_fn (k->functions) && is_overloaded_fn (fn)) k->functions = build_overload (fn, k->functions); else { tree f1 = OVL_CURRENT (k->functions); tree f2 = fn; if (is_overloaded_fn (f1)) { fn = f1; f1 = f2; f2 = fn; } error ("%q+D is not a function,", f1); error (" conflict with %q+D", f2); error (" in call to %qD", k->name); return true; } return false; } /* Returns true iff CURRENT has declared itself to be an associated namespace of SCOPE via a strong using-directive (or transitive chain thereof). Both are namespaces. */ bool is_associated_namespace (tree current, tree scope) { tree seen = NULL_TREE; tree todo = NULL_TREE; tree t; while (1) { if (scope == current) return true; seen = tree_cons (scope, NULL_TREE, seen); for (t = DECL_NAMESPACE_ASSOCIATIONS (scope); t; t = TREE_CHAIN (t)) if (!purpose_member (TREE_PURPOSE (t), seen)) todo = tree_cons (TREE_PURPOSE (t), NULL_TREE, todo); if (todo) { scope = TREE_PURPOSE (todo); todo = TREE_CHAIN (todo); } else return false; } } /* Return whether FN is a friend of an associated class of ARG. */ static bool friend_of_associated_class_p (tree arg, tree fn) { tree type; if (TYPE_P (arg)) type = arg; else if (type_unknown_p (arg)) return false; else type = TREE_TYPE (arg); /* If TYPE is a class, the class itself and all base classes are associated classes. */ if (CLASS_TYPE_P (type)) { if (is_friend (type, fn)) return true; if (TYPE_BINFO (type)) { tree binfo, base_binfo; int i; for (binfo = TYPE_BINFO (type), i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) if (is_friend (BINFO_TYPE (base_binfo), fn)) return true; } } /* If TYPE is a class member, the class of which it is a member is an associated class. */ if ((CLASS_TYPE_P (type) || TREE_CODE (type) == UNION_TYPE || TREE_CODE (type) == ENUMERAL_TYPE) && TYPE_CONTEXT (type) && CLASS_TYPE_P (TYPE_CONTEXT (type)) && is_friend (TYPE_CONTEXT (type), fn)) return true; return false; } /* Add functions of a namespace to the lookup structure. Returns true on error. */ static bool arg_assoc_namespace (struct arg_lookup *k, tree scope) { tree value; if (purpose_member (scope, k->namespaces)) return 0; k->namespaces = tree_cons (scope, NULL_TREE, k->namespaces); /* Check out our super-users. */ for (value = DECL_NAMESPACE_ASSOCIATIONS (scope); value; value = TREE_CHAIN (value)) if (arg_assoc_namespace (k, TREE_PURPOSE (value))) return true; value = namespace_binding (k->name, scope); if (!value) return false; for (; value; value = OVL_NEXT (value)) { /* We don't want to find arbitrary hidden functions via argument dependent lookup. We only want to find friends of associated classes. */ if (hidden_name_p (OVL_CURRENT (value))) { tree args; for (args = k->args; args; args = TREE_CHAIN (args)) if (friend_of_associated_class_p (TREE_VALUE (args), OVL_CURRENT (value))) break; if (!args) continue; } if (add_function (k, OVL_CURRENT (value))) return true; } return false; } /* Adds everything associated with a template argument to the lookup structure. Returns true on error. */ static bool arg_assoc_template_arg (struct arg_lookup *k, tree arg) { /* [basic.lookup.koenig] If T is a template-id, its associated namespaces and classes are ... the namespaces and classes associated with the types of the template arguments provided for template type parameters (excluding template template parameters); the namespaces in which any template template arguments are defined; and the classes in which any member templates used as template template arguments are defined. [Note: non-type template arguments do not contribute to the set of associated namespaces. ] */ /* Consider first template template arguments. */ if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE) return false; else if (TREE_CODE (arg) == TEMPLATE_DECL) { tree ctx = CP_DECL_CONTEXT (arg); /* It's not a member template. */ if (TREE_CODE (ctx) == NAMESPACE_DECL) return arg_assoc_namespace (k, ctx); /* Otherwise, it must be member template. */ else return arg_assoc_class (k, ctx); } /* It's an argument pack; handle it recursively. */ else if (ARGUMENT_PACK_P (arg)) { tree args = ARGUMENT_PACK_ARGS (arg); int i, len = TREE_VEC_LENGTH (args); for (i = 0; i < len; ++i) if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, i))) return true; return false; } /* It's not a template template argument, but it is a type template argument. */ else if (TYPE_P (arg)) return arg_assoc_type (k, arg); /* It's a non-type template argument. */ else return false; } /* Adds everything associated with class to the lookup structure. Returns true on error. */ static bool arg_assoc_class (struct arg_lookup *k, tree type) { tree list, friends, context; int i; /* Backend build structures, such as __builtin_va_list, aren't affected by all this. */ if (!CLASS_TYPE_P (type)) return false; if (purpose_member (type, k->classes)) return false; k->classes = tree_cons (type, NULL_TREE, k->classes); context = decl_namespace_context (type); if (arg_assoc_namespace (k, context)) return true; if (TYPE_BINFO (type)) { /* Process baseclasses. */ tree binfo, base_binfo; for (binfo = TYPE_BINFO (type), i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) if (arg_assoc_class (k, BINFO_TYPE (base_binfo))) return true; } /* Process friends. */ for (list = DECL_FRIENDLIST (TYPE_MAIN_DECL (type)); list; list = TREE_CHAIN (list)) if (k->name == FRIEND_NAME (list)) for (friends = FRIEND_DECLS (list); friends; friends = TREE_CHAIN (friends)) { tree fn = TREE_VALUE (friends); /* Only interested in global functions with potentially hidden (i.e. unqualified) declarations. */ if (CP_DECL_CONTEXT (fn) != context) continue; /* Template specializations are never found by name lookup. (Templates themselves can be found, but not template specializations.) */ if (TREE_CODE (fn) == FUNCTION_DECL && DECL_USE_TEMPLATE (fn)) continue; if (add_function (k, fn)) return true; } /* Process template arguments. */ if (CLASSTYPE_TEMPLATE_INFO (type) && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))) { list = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)); for (i = 0; i < TREE_VEC_LENGTH (list); ++i) arg_assoc_template_arg (k, TREE_VEC_ELT (list, i)); } return false; } /* Adds everything associated with a given type. Returns 1 on error. */ static bool arg_assoc_type (struct arg_lookup *k, tree type) { /* As we do not get the type of non-type dependent expressions right, we can end up with such things without a type. */ if (!type) return false; if (TYPE_PTRMEM_P (type)) { /* Pointer to member: associate class type and value type. */ if (arg_assoc_type (k, TYPE_PTRMEM_CLASS_TYPE (type))) return true; return arg_assoc_type (k, TYPE_PTRMEM_POINTED_TO_TYPE (type)); } else switch (TREE_CODE (type)) { case ERROR_MARK: return false; case VOID_TYPE: case INTEGER_TYPE: case REAL_TYPE: case COMPLEX_TYPE: case VECTOR_TYPE: case BOOLEAN_TYPE: return false; case RECORD_TYPE: if (TYPE_PTRMEMFUNC_P (type)) return arg_assoc_type (k, TYPE_PTRMEMFUNC_FN_TYPE (type)); return arg_assoc_class (k, type); case POINTER_TYPE: case REFERENCE_TYPE: case ARRAY_TYPE: return arg_assoc_type (k, TREE_TYPE (type)); case UNION_TYPE: case ENUMERAL_TYPE: return arg_assoc_namespace (k, decl_namespace_context (type)); case METHOD_TYPE: /* The basetype is referenced in the first arg type, so just fall through. */ case FUNCTION_TYPE: /* Associate the parameter types. */ if (arg_assoc_args (k, TYPE_ARG_TYPES (type))) return true; /* Associate the return type. */ return arg_assoc_type (k, TREE_TYPE (type)); case TEMPLATE_TYPE_PARM: case BOUND_TEMPLATE_TEMPLATE_PARM: return false; case TYPENAME_TYPE: return false; case LANG_TYPE: gcc_assert (type == unknown_type_node); return false; case TYPE_PACK_EXPANSION: return arg_assoc_type (k, PACK_EXPANSION_PATTERN (type)); default: gcc_unreachable (); } return false; } /* Adds everything associated with arguments. Returns true on error. */ static bool arg_assoc_args (struct arg_lookup *k, tree args) { for (; args; args = TREE_CHAIN (args)) if (arg_assoc (k, TREE_VALUE (args))) return true; return false; } /* Adds everything associated with a given tree_node. Returns 1 on error. */ static bool arg_assoc (struct arg_lookup *k, tree n) { if (n == error_mark_node) return false; if (TYPE_P (n)) return arg_assoc_type (k, n); if (! type_unknown_p (n)) return arg_assoc_type (k, TREE_TYPE (n)); if (TREE_CODE (n) == ADDR_EXPR) n = TREE_OPERAND (n, 0); if (TREE_CODE (n) == COMPONENT_REF) n = TREE_OPERAND (n, 1); if (TREE_CODE (n) == OFFSET_REF) n = TREE_OPERAND (n, 1); while (TREE_CODE (n) == TREE_LIST) n = TREE_VALUE (n); if (TREE_CODE (n) == BASELINK) n = BASELINK_FUNCTIONS (n); if (TREE_CODE (n) == FUNCTION_DECL) return arg_assoc_type (k, TREE_TYPE (n)); if (TREE_CODE (n) == TEMPLATE_ID_EXPR) { /* [basic.lookup.koenig] If T is a template-id, its associated namespaces and classes are the namespace in which the template is defined; for member templates, the member template's class... */ tree template = TREE_OPERAND (n, 0); tree args = TREE_OPERAND (n, 1); tree ctx; int ix; if (TREE_CODE (template) == COMPONENT_REF) template = TREE_OPERAND (template, 1); /* First, the template. There may actually be more than one if this is an overloaded function template. But, in that case, we only need the first; all the functions will be in the same namespace. */ template = OVL_CURRENT (template); ctx = CP_DECL_CONTEXT (template); if (TREE_CODE (ctx) == NAMESPACE_DECL) { if (arg_assoc_namespace (k, ctx) == 1) return true; } /* It must be a member template. */ else if (arg_assoc_class (k, ctx) == 1) return true; /* Now the arguments. */ if (args) for (ix = TREE_VEC_LENGTH (args); ix--;) if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, ix)) == 1) return true; } else if (TREE_CODE (n) == OVERLOAD) { for (; n; n = OVL_CHAIN (n)) if (arg_assoc_type (k, TREE_TYPE (OVL_FUNCTION (n)))) return true; } return false; } /* Performs Koenig lookup depending on arguments, where fns are the functions found in normal lookup. */ tree lookup_arg_dependent (tree name, tree fns, tree args) { struct arg_lookup k; timevar_push (TV_NAME_LOOKUP); /* Remove any hidden friend functions from the list of functions found so far. They will be added back by arg_assoc_class as appropriate. */ fns = remove_hidden_names (fns); k.name = name; k.args = args; k.functions = fns; k.classes = NULL_TREE; /* We previously performed an optimization here by setting NAMESPACES to the current namespace when it was safe. However, DR 164 says that namespaces that were already searched in the first stage of template processing are searched again (potentially picking up later definitions) in the second stage. */ k.namespaces = NULL_TREE; arg_assoc_args (&k, args); fns = k.functions; if (fns && TREE_CODE (fns) != VAR_DECL && !is_overloaded_fn (fns)) { error ("argument dependent lookup finds %q+D", fns); error (" in call to %qD", name); fns = error_mark_node; } POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, fns); } /* Add namespace to using_directives. Return NULL_TREE if nothing was changed (i.e. there was already a directive), or the fresh TREE_LIST otherwise. */ static tree push_using_directive (tree used) { tree ud = current_binding_level->using_directives; tree iter, ancestor; timevar_push (TV_NAME_LOOKUP); /* Check if we already have this. */ if (purpose_member (used, ud) != NULL_TREE) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, NULL_TREE); ancestor = namespace_ancestor (current_decl_namespace (), used); ud = current_binding_level->using_directives; ud = tree_cons (used, ancestor, ud); current_binding_level->using_directives = ud; /* Recursively add all namespaces used. */ for (iter = DECL_NAMESPACE_USING (used); iter; iter = TREE_CHAIN (iter)) push_using_directive (TREE_PURPOSE (iter)); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, ud); } /* The type TYPE is being declared. If it is a class template, or a specialization of a class template, do any processing required and perform error-checking. If IS_FRIEND is nonzero, this TYPE is being declared a friend. B is the binding level at which this TYPE should be bound. Returns the TYPE_DECL for TYPE, which may have been altered by this processing. */ static tree maybe_process_template_type_declaration (tree type, int is_friend, cxx_scope *b) { tree decl = TYPE_NAME (type); if (processing_template_parmlist) /* You can't declare a new template type in a template parameter list. But, you can declare a non-template type: template struct S; is a forward-declaration of `A'. */ ; else if (b->kind == sk_namespace && current_binding_level->kind != sk_namespace) /* If this new type is being injected into a containing scope, then it's not a template type. */ ; else { gcc_assert (IS_AGGR_TYPE (type) || TREE_CODE (type) == ENUMERAL_TYPE); if (processing_template_decl) { /* This may change after the call to push_template_decl_real, but we want the original value. */ tree name = DECL_NAME (decl); decl = push_template_decl_real (decl, is_friend); /* If the current binding level is the binding level for the template parameters (see the comment in begin_template_parm_list) and the enclosing level is a class scope, and we're not looking at a friend, push the declaration of the member class into the class scope. In the friend case, push_template_decl will already have put the friend into global scope, if appropriate. */ if (TREE_CODE (type) != ENUMERAL_TYPE && !is_friend && b->kind == sk_template_parms && b->level_chain->kind == sk_class) { finish_member_declaration (CLASSTYPE_TI_TEMPLATE (type)); if (!COMPLETE_TYPE_P (current_class_type)) { maybe_add_class_template_decl_list (current_class_type, type, /*friend_p=*/0); /* Put this UTD in the table of UTDs for the class. */ if (CLASSTYPE_NESTED_UTDS (current_class_type) == NULL) CLASSTYPE_NESTED_UTDS (current_class_type) = binding_table_new (SCOPE_DEFAULT_HT_SIZE); binding_table_insert (CLASSTYPE_NESTED_UTDS (current_class_type), name, type); } } } } return decl; } /* Push a tag name NAME for struct/class/union/enum type TYPE. In case that the NAME is a class template, the tag is processed but not pushed. The pushed scope depend on the SCOPE parameter: - When SCOPE is TS_CURRENT, put it into the inner-most non-sk_cleanup scope. - When SCOPE is TS_GLOBAL, put it in the inner-most non-class and non-template-parameter scope. This case is needed for forward declarations. - When SCOPE is TS_WITHIN_ENCLOSING_NON_CLASS, this is similar to TS_GLOBAL case except that names within template-parameter scopes are not pushed at all. Returns TYPE upon success and ERROR_MARK_NODE otherwise. */ tree pushtag (tree name, tree type, tag_scope scope) { struct cp_binding_level *b; tree decl; timevar_push (TV_NAME_LOOKUP); b = current_binding_level; while (/* Cleanup scopes are not scopes from the point of view of the language. */ b->kind == sk_cleanup /* Neither are the scopes used to hold template parameters for an explicit specialization. For an ordinary template declaration, these scopes are not scopes from the point of view of the language. */ || (b->kind == sk_template_parms && (b->explicit_spec_p || scope == ts_global)) || (b->kind == sk_class && (scope != ts_current /* We may be defining a new type in the initializer of a static member variable. We allow this when not pedantic, and it is particularly useful for type punning via an anonymous union. */ || COMPLETE_TYPE_P (b->this_entity)))) b = b->level_chain; gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE); /* Do C++ gratuitous typedefing. */ if (IDENTIFIER_TYPE_VALUE (name) != type) { tree tdef; int in_class = 0; tree context = TYPE_CONTEXT (type); if (! context) { tree cs = current_scope (); if (scope == ts_current) context = cs; else if (cs != NULL_TREE && TYPE_P (cs)) /* When declaring a friend class of a local class, we want to inject the newly named class into the scope containing the local class, not the namespace scope. */ context = decl_function_context (get_type_decl (cs)); } if (!context) context = current_namespace; if (b->kind == sk_class || (b->kind == sk_template_parms && b->level_chain->kind == sk_class)) in_class = 1; if (current_lang_name == lang_name_java) TYPE_FOR_JAVA (type) = 1; tdef = create_implicit_typedef (name, type); DECL_CONTEXT (tdef) = FROB_CONTEXT (context); if (scope == ts_within_enclosing_non_class) { /* This is a friend. Make this TYPE_DECL node hidden from ordinary name lookup. Its corresponding TEMPLATE_DECL will be marked in push_template_decl_real. */ retrofit_lang_decl (tdef); DECL_ANTICIPATED (tdef) = 1; DECL_FRIEND_P (tdef) = 1; } decl = maybe_process_template_type_declaration (type, scope == ts_within_enclosing_non_class, b); if (decl == error_mark_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, decl); if (b->kind == sk_class) { if (!PROCESSING_REAL_TEMPLATE_DECL_P ()) /* Put this TYPE_DECL on the TYPE_FIELDS list for the class. But if it's a member template class, we want the TEMPLATE_DECL, not the TYPE_DECL, so this is done later. */ finish_member_declaration (decl); else pushdecl_class_level (decl); } else if (b->kind != sk_template_parms) { decl = pushdecl_with_scope (decl, b, /*is_friend=*/false); if (decl == error_mark_node) POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, decl); } if (! in_class) set_identifier_type_value_with_scope (name, tdef, b); TYPE_CONTEXT (type) = DECL_CONTEXT (decl); /* If this is a local class, keep track of it. We need this information for name-mangling, and so that it is possible to find all function definitions in a translation unit in a convenient way. (It's otherwise tricky to find a member function definition it's only pointed to from within a local class.) */ if (TYPE_CONTEXT (type) && TREE_CODE (TYPE_CONTEXT (type)) == FUNCTION_DECL) VEC_safe_push (tree, gc, local_classes, type); } if (b->kind == sk_class && !COMPLETE_TYPE_P (current_class_type)) { maybe_add_class_template_decl_list (current_class_type, type, /*friend_p=*/0); if (CLASSTYPE_NESTED_UTDS (current_class_type) == NULL) CLASSTYPE_NESTED_UTDS (current_class_type) = binding_table_new (SCOPE_DEFAULT_HT_SIZE); binding_table_insert (CLASSTYPE_NESTED_UTDS (current_class_type), name, type); } decl = TYPE_NAME (type); gcc_assert (TREE_CODE (decl) == TYPE_DECL); TYPE_STUB_DECL (type) = decl; /* Set type visibility now if this is a forward declaration. */ TREE_PUBLIC (decl) = 1; determine_visibility (decl); POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, type); } /* Subroutines for reverting temporarily to top-level for instantiation of templates and such. We actually need to clear out the class- and local-value slots of all identifiers, so that only the global values are at all visible. Simply setting current_binding_level to the global scope isn't enough, because more binding levels may be pushed. */ struct saved_scope *scope_chain; /* If ID has not already been marked, add an appropriate binding to *OLD_BINDINGS. */ static void store_binding (tree id, VEC(cxx_saved_binding,gc) **old_bindings) { cxx_saved_binding *saved; if (!id || !IDENTIFIER_BINDING (id)) return; if (IDENTIFIER_MARKED (id)) return; IDENTIFIER_MARKED (id) = 1; saved = VEC_safe_push (cxx_saved_binding, gc, *old_bindings, NULL); saved->identifier = id; saved->binding = IDENTIFIER_BINDING (id); saved->real_type_value = REAL_IDENTIFIER_TYPE_VALUE (id); IDENTIFIER_BINDING (id) = NULL; } static void store_bindings (tree names, VEC(cxx_saved_binding,gc) **old_bindings) { tree t; timevar_push (TV_NAME_LOOKUP); for (t = names; t; t = TREE_CHAIN (t)) { tree id; if (TREE_CODE (t) == TREE_LIST) id = TREE_PURPOSE (t); else id = DECL_NAME (t); store_binding (id, old_bindings); } timevar_pop (TV_NAME_LOOKUP); } /* Like store_bindings, but NAMES is a vector of cp_class_binding objects, rather than a TREE_LIST. */ static void store_class_bindings (VEC(cp_class_binding,gc) *names, VEC(cxx_saved_binding,gc) **old_bindings) { size_t i; cp_class_binding *cb; timevar_push (TV_NAME_LOOKUP); for (i = 0; VEC_iterate(cp_class_binding, names, i, cb); ++i) store_binding (cb->identifier, old_bindings); timevar_pop (TV_NAME_LOOKUP); } void push_to_top_level (void) { struct saved_scope *s; struct cp_binding_level *b; cxx_saved_binding *sb; size_t i; bool need_pop; timevar_push (TV_NAME_LOOKUP); s = GGC_CNEW (struct saved_scope); b = scope_chain ? current_binding_level : 0; /* If we're in the middle of some function, save our state. */ if (cfun) { need_pop = true; push_function_context_to (NULL_TREE); } else need_pop = false; if (scope_chain && previous_class_level) store_class_bindings (previous_class_level->class_shadowed, &s->old_bindings); /* Have to include the global scope, because class-scope decls aren't listed anywhere useful. */ for (; b; b = b->level_chain) { tree t; /* Template IDs are inserted into the global level. If they were inserted into namespace level, finish_file wouldn't find them when doing pending instantiations. Therefore, don't stop at namespace level, but continue until :: . */ if (global_scope_p (b)) break; store_bindings (b->names, &s->old_bindings); /* We also need to check class_shadowed to save class-level type bindings, since pushclass doesn't fill in b->names. */ if (b->kind == sk_class) store_class_bindings (b->class_shadowed, &s->old_bindings); /* Unwind type-value slots back to top level. */ for (t = b->type_shadowed; t; t = TREE_CHAIN (t)) SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (t), TREE_VALUE (t)); } for (i = 0; VEC_iterate (cxx_saved_binding, s->old_bindings, i, sb); ++i) IDENTIFIER_MARKED (sb->identifier) = 0; s->prev = scope_chain; s->bindings = b; s->need_pop_function_context = need_pop; s->function_decl = current_function_decl; s->skip_evaluation = skip_evaluation; scope_chain = s; current_function_decl = NULL_TREE; current_lang_base = VEC_alloc (tree, gc, 10); current_lang_name = lang_name_cplusplus; current_namespace = global_namespace; push_class_stack (); skip_evaluation = 0; timevar_pop (TV_NAME_LOOKUP); } void pop_from_top_level (void) { struct saved_scope *s = scope_chain; cxx_saved_binding *saved; size_t i; timevar_push (TV_NAME_LOOKUP); /* Clear out class-level bindings cache. */ if (previous_class_level) invalidate_class_lookup_cache (); pop_class_stack (); current_lang_base = 0; scope_chain = s->prev; for (i = 0; VEC_iterate (cxx_saved_binding, s->old_bindings, i, saved); ++i) { tree id = saved->identifier; IDENTIFIER_BINDING (id) = saved->binding; SET_IDENTIFIER_TYPE_VALUE (id, saved->real_type_value); } /* If we were in the middle of compiling a function, restore our state. */ if (s->need_pop_function_context) pop_function_context_from (NULL_TREE); current_function_decl = s->function_decl; skip_evaluation = s->skip_evaluation; timevar_pop (TV_NAME_LOOKUP); } /* Pop off extraneous binding levels left over due to syntax errors. We don't pop past namespaces, as they might be valid. */ void pop_everything (void) { if (ENABLE_SCOPE_CHECKING) verbatim ("XXX entering pop_everything ()\n"); while (!toplevel_bindings_p ()) { if (current_binding_level->kind == sk_class) pop_nested_class (); else poplevel (0, 0, 0); } if (ENABLE_SCOPE_CHECKING) verbatim ("XXX leaving pop_everything ()\n"); } /* Emit debugging information for using declarations and directives. If input tree is overloaded fn then emit debug info for all candidates. */ void cp_emit_debug_info_for_using (tree t, tree context) { /* Don't try to emit any debug information if we have errors. */ if (sorrycount || errorcount) return; /* Ignore this FUNCTION_DECL if it refers to a builtin declaration of a builtin function. */ if (TREE_CODE (t) == FUNCTION_DECL && DECL_EXTERNAL (t) && DECL_BUILT_IN (t)) return; /* Do not supply context to imported_module_or_decl, if it is a global namespace. */ if (context == global_namespace) context = NULL_TREE; if (BASELINK_P (t)) t = BASELINK_FUNCTIONS (t); /* FIXME: Handle TEMPLATE_DECLs. */ for (t = OVL_CURRENT (t); t; t = OVL_NEXT (t)) if (TREE_CODE (t) != TEMPLATE_DECL) (*debug_hooks->imported_module_or_decl) (t, context); } #include "gt-cp-name-lookup.h"