gcc/tree-vector-builder.cc


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/* A class for building vector tree constants.
   Copyright (C) 2017-2022 Free Software Foundation, Inc.

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
<http://www.gnu.org/licenses/>.  */

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tree.h"
#include "fold-const.h"
#include "tree-vector-builder.h"

/* Return a vector element with the value BASE + FACTOR * STEP.  */

tree
tree_vector_builder::apply_step (tree base, unsigned int factor,
				 const wide_int &step) const
{
  return wide_int_to_tree (TREE_TYPE (base),
			   wi::to_wide (base) + factor * step);
}

/* Return a VECTOR_CST for the current constant.  */

tree
tree_vector_builder::build ()
{
  finalize ();
  gcc_assert (pow2p_hwi (npatterns ()));
  tree v = make_vector (exact_log2 (npatterns ()), nelts_per_pattern ());
  TREE_TYPE (v) = m_type;
  memcpy (VECTOR_CST_ENCODED_ELTS (v), address (),
	  encoded_nelts () * sizeof (tree));
  return v;
}
/* Process declarations and variables for C compiler.
   Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   2001, 2002 Free Software Foundation, Inc.

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 2, 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 COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.  */

/* Process declarations and symbol lookup for C front end.
   Also constructs types; the standard scalar types at initialization,
   and structure, union, array and enum types when they are declared.  */

/* ??? not all decl nodes are given the most useful possible
   line numbers.  For example, the CONST_DECLs for enum values.  */

#include "config.h"
#include "system.h"
#include "intl.h"
#include "tree.h"
#include "tree-inline.h"
#include "rtl.h"
#include "flags.h"
#include "function.h"
#include "output.h"
#include "expr.h"
#include "c-tree.h"
#include "c-lex.h"
#include "toplev.h"
#include "ggc.h"
#include "tm_p.h"
#include "cpplib.h"
#include "target.h"
#include "debug.h"
#include "timevar.h"
#include "c-common.h"
#include "c-pragma.h"

/* In grokdeclarator, distinguish syntactic contexts of declarators.  */
enum decl_context
{ NORMAL,			/* Ordinary declaration */
  FUNCDEF,			/* Function definition */
  PARM,				/* Declaration of parm before function body */
  FIELD,			/* Declaration inside struct or union */
  BITFIELD,			/* Likewise but with specified width */
  TYPENAME};			/* Typename (inside cast or sizeof)  */


/* Nonzero if we have seen an invalid cross reference
   to a struct, union, or enum, but not yet printed the message.  */

tree pending_invalid_xref;
/* File and line to appear in the eventual error message.  */
const char *pending_invalid_xref_file;
int pending_invalid_xref_line;

/* While defining an enum type, this is 1 plus the last enumerator
   constant value.  Note that will do not have to save this or `enum_overflow'
   around nested function definition since such a definition could only
   occur in an enum value expression and we don't use these variables in
   that case.  */

static tree enum_next_value;

/* Nonzero means that there was overflow computing enum_next_value.  */

static int enum_overflow;

/* Parsing a function declarator leaves a list of parameter names
   or a chain or parameter decls here.  */

static tree last_function_parms;

/* Parsing a function declarator leaves here a chain of structure
   and enum types declared in the parmlist.  */

static tree last_function_parm_tags;

/* After parsing the declarator that starts a function definition,
   `start_function' puts here the list of parameter names or chain of decls.
   `store_parm_decls' finds it here.  */

static tree current_function_parms;

/* Similar, for last_function_parm_tags.  */
static tree current_function_parm_tags;

/* Similar, for the file and line that the prototype came from if this is
   an old-style definition.  */
static const char *current_function_prototype_file;
static int current_function_prototype_line;

/* The current statement tree.  */

static struct stmt_tree_s c_stmt_tree;

/* The current scope statement stack.  */

static tree c_scope_stmt_stack;

/* A list (chain of TREE_LIST nodes) of all LABEL_DECLs in the function
   that have names.  Here so we can clear out their names' definitions
   at the end of the function.  */

static tree named_labels;

/* A list of LABEL_DECLs from outer contexts that are currently shadowed.  */

static tree shadowed_labels;

/* Nonzero when store_parm_decls is called indicates a varargs function.
   Value not meaningful after store_parm_decls.  */

static int c_function_varargs;

/* Set to 0 at beginning of a function definition, set to 1 if
   a return statement that specifies a return value is seen.  */

int current_function_returns_value;

/* Set to 0 at beginning of a function definition, set to 1 if
   a return statement with no argument is seen.  */

int current_function_returns_null;

/* Set to 0 at beginning of a function definition, set to 1 if
   a call to a noreturn function is seen.  */

int current_function_returns_abnormally;

/* Set to nonzero by `grokdeclarator' for a function
   whose return type is defaulted, if warnings for this are desired.  */

static int warn_about_return_type;

/* Nonzero when starting a function declared `extern inline'.  */

static int current_extern_inline;

/* For each binding contour we allocate a binding_level structure
 * which records the names defined in that contour.
 * Contours include:
 *  0) the global one
 *  1) one for each function definition,
 *     where internal declarations of the parameters appear.
 *  2) one for each compound statement,
 *     to record its declarations.
 *
 * The current meaning of a name can be found by searching the levels from
 * the current one out to the global one.
 */

/* Note that the information in the `names' component of the global contour
   is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers.  */

struct binding_level
  {
    /* A chain of _DECL nodes for all variables, constants, functions,
       and typedef types.  These are in the reverse of the order supplied.
     */
    tree names;

    /* A list of structure, union and enum definitions,
     * for looking up tag names.
     * It is a chain of TREE_LIST nodes, each of whose TREE_PURPOSE is a name,
     * or NULL_TREE; and whose TREE_VALUE is a RECORD_TYPE, UNION_TYPE,
     * or ENUMERAL_TYPE node.
     */
    tree tags;

    /* For each level, a list of shadowed outer-level local definitions
       to be restored when this level is popped.
       Each link is a TREE_LIST whose TREE_PURPOSE is an identifier and
       whose TREE_VALUE is its old definition (a kind of ..._DECL node).  */
    tree shadowed;

    /* For each level (except not the global one),
       a chain of BLOCK nodes for all the levels
       that were entered and exited one level down.  */
    tree blocks;

    /* The BLOCK node for this level, if one has been preallocated.
       If 0, the BLOCK is allocated (if needed) when the level is popped.  */
    tree this_block;

    /* The binding level which this one is contained in (inherits from).  */
    struct binding_level *level_chain;

    /* Nonzero for the level that holds the parameters of a function.  */
    char parm_flag;

    /* Nonzero if this level "doesn't exist" for tags.  */
    char tag_transparent;

    /* Nonzero if sublevels of this level "don't exist" for tags.
       This is set in the parm level of a function definition
       while reading the function body, so that the outermost block
       of the function body will be tag-transparent.  */
    char subblocks_tag_transparent;

    /* Nonzero means make a BLOCK for this level regardless of all else.  */
    char keep;

    /* Nonzero means make a BLOCK if this level has any subblocks.  */
    char keep_if_subblocks;

    /* Number of decls in `names' that have incomplete
       structure or union types.  */
    int n_incomplete;

    /* A list of decls giving the (reversed) specified order of parms,
       not including any forward-decls in the parmlist.
       This is so we can put the parms in proper order for assign_parms.  */
    tree parm_order;
  };

#define NULL_BINDING_LEVEL (struct binding_level *) NULL

/* The binding level currently in effect.  */

static struct binding_level *current_binding_level;

/* A chain of binding_level structures awaiting reuse.  */

static struct binding_level *free_binding_level;

/* The outermost binding level, for names of file scope.
   This is created when the compiler is started and exists
   through the entire run.  */

static struct binding_level *global_binding_level;

/* Binding level structures are initialized by copying this one.  */

static struct binding_level clear_binding_level
  = {NULL, NULL, NULL, NULL, NULL, NULL_BINDING_LEVEL, 0, 0, 0, 0, 0, 0,
     NULL};

/* Nonzero means unconditionally make a BLOCK for the next level pushed.  */

static int keep_next_level_flag;

/* Nonzero means make a BLOCK for the next level pushed
   if it has subblocks.  */

static int keep_next_if_subblocks;

/* The chain of outer levels of label scopes.
   This uses the same data structure used for binding levels,
   but it works differently: each link in the chain records
   saved values of named_labels and shadowed_labels for
   a label binding level outside the current one.  */

static struct binding_level *label_level_chain;

/* Functions called automatically at the beginning and end of execution.  */

tree static_ctors, static_dtors;

/* Forward declarations.  */

static struct binding_level * make_binding_level	PARAMS ((void));
static void mark_binding_level		PARAMS ((void *));
static void clear_limbo_values		PARAMS ((tree));
static int duplicate_decls		PARAMS ((tree, tree, int));
static int redeclaration_error_message	PARAMS ((tree, tree));
static void storedecls			PARAMS ((tree));
static void storetags			PARAMS ((tree));
static tree lookup_tag			PARAMS ((enum tree_code, tree,
						 struct binding_level *, int));
static tree lookup_tag_reverse		PARAMS ((tree));
static tree grokdeclarator		PARAMS ((tree, tree, enum decl_context,
						 int));
static tree grokparms			PARAMS ((tree, int));
static void layout_array_type		PARAMS ((tree));
static tree c_make_fname_decl           PARAMS ((tree, int));
static void c_expand_body               PARAMS ((tree, int, int));
static void warn_if_shadowing		PARAMS ((tree, tree));

/* C-specific option variables.  */

/* Nonzero means allow type mismatches in conditional expressions;
   just make their values `void'.  */

int flag_cond_mismatch;

/* Nonzero means don't recognize the keyword `asm'.  */

int flag_no_asm;

/* Nonzero means enable C89 Amendment 1 features.  */

int flag_isoc94 = 0;

/* Nonzero means use the ISO C99 dialect of C.  */

int flag_isoc99 = 0;

/* Nonzero means that we have builtin functions, and main is an int */

int flag_hosted = 1;

/* Nonzero means add default format_arg attributes for functions not
   in ISO C.  */

int flag_noniso_default_format_attributes = 1;

/* Nonzero means to treat bitfields as signed unless they say `unsigned'.  */

int flag_signed_bitfields = 1;
int explicit_flag_signed_bitfields = 0;

/* Nonzero means warn about use of implicit int.  */

int warn_implicit_int;

/* Nonzero means warn about usage of long long when `-pedantic'.  */

int warn_long_long = 1;

/* Nonzero means message about use of implicit function declarations;
 1 means warning; 2 means error.  */

int mesg_implicit_function_declaration = -1;

/* Nonzero means give string constants the type `const char *'
   to get extra warnings from them.  These warnings will be too numerous
   to be useful, except in thoroughly ANSIfied programs.  */

int flag_const_strings;

/* Nonzero means warn about pointer casts that can drop a type qualifier
   from the pointer target type.  */

int warn_cast_qual;

/* Nonzero means warn when casting a function call to a type that does
   not match the return type (e.g. (float)sqrt() or (anything*)malloc()
   when there is no previous declaration of sqrt or malloc.  */

int warn_bad_function_cast;

/* Warn about functions which might be candidates for format attributes.  */

int warn_missing_format_attribute;

/* Warn about traditional constructs whose meanings changed in ANSI C.  */

int warn_traditional;

/* Nonzero means warn about sizeof(function) or addition/subtraction
   of function pointers.  */

int warn_pointer_arith;

/* Nonzero means warn for non-prototype function decls
   or non-prototyped defs without previous prototype.  */

int warn_strict_prototypes;

/* Nonzero means warn for any global function def
   without separate previous prototype decl.  */

int warn_missing_prototypes;

/* Nonzero means warn for any global function def
   without separate previous decl.  */

int warn_missing_declarations;

/* Nonzero means warn about multiple (redundant) decls for the same single
   variable or function.  */

int warn_redundant_decls = 0;

/* Nonzero means warn about extern declarations of objects not at
   file-scope level and about *all* declarations of functions (whether
   extern or static) not at file-scope level.  Note that we exclude
   implicit function declarations.  To get warnings about those, use
   -Wimplicit.  */

int warn_nested_externs = 0;

/* Warn about a subscript that has type char.  */

int warn_char_subscripts = 0;

/* Warn if a type conversion is done that might have confusing results.  */

int warn_conversion;

/* Warn if adding () is suggested.  */

int warn_parentheses;

/* Warn if initializer is not completely bracketed.  */

int warn_missing_braces;

/* Warn if main is suspicious.  */

int warn_main;

/* Warn about #pragma directives that are not recognised.  */

int warn_unknown_pragmas = 0; /* Tri state variable.  */

/* Warn about comparison of signed and unsigned values.
   If -1, neither -Wsign-compare nor -Wno-sign-compare has been specified.  */

int warn_sign_compare = -1;

/* Warn about testing equality of floating point numbers.  */

int warn_float_equal = 0;

/* Nonzero means `$' can be in an identifier.  */

#ifndef DOLLARS_IN_IDENTIFIERS
#define DOLLARS_IN_IDENTIFIERS 1
#endif
int dollars_in_ident = DOLLARS_IN_IDENTIFIERS;

/* States indicating how grokdeclarator() should handle declspecs marked
   with __attribute__((deprecated)).  An object declared as
   __attribute__((deprecated)) suppresses warnings of uses of other
   deprecated items.  */
   
enum deprecated_states {
  DEPRECATED_NORMAL,
  DEPRECATED_SUPPRESS
};

static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;

/* Decode the string P as a language-specific option for C.
   Return the number of strings consumed.  Should not complain
   if it does not recognise the option.  */

int
c_decode_option (argc, argv)
     int argc ATTRIBUTE_UNUSED;
     char **argv;
{
  int strings_processed;
  char *p = argv[0];

  static const struct {
      /* The name of the option.  */
      const char *option;
      /* If non-NULL, a flag variable to set to 0 or 1.  If NULL,
         this means that cpp handles this option.  */
      int *flag;
  } warn_options[] = {
    /* This list is in alphabetical order.  Keep it like that.  */
    { "bad-function-cast", &warn_bad_function_cast },
    { "cast-qual", &warn_cast_qual },
    { "char-subscripts", &warn_char_subscripts },
    { "comment", NULL },
    { "comments", NULL },
    { "conversion", &warn_conversion },
    { "div-by-zero", &warn_div_by_zero },
    { "float-equal", &warn_float_equal },
    { "format-extra-args", &warn_format_extra_args },
    { "format-zero-length", &warn_format_zero_length },
    { "format-nonliteral", &warn_format_nonliteral },
    { "format-security", &warn_format_security },
    { "format-y2k", &warn_format_y2k },
    { "implicit-function-declaration", &mesg_implicit_function_declaration },
    { "implicit-int", &warn_implicit_int },
    { "import", NULL },
    { "long-long", &warn_long_long },
    { "main", &warn_main },
    { "missing-braces", &warn_missing_braces },
    { "missing-declarations", &warn_missing_declarations },
    { "missing-format-attribute", &warn_missing_format_attribute },
    { "missing-prototypes", &warn_missing_prototypes },
    { "multichar", &warn_multichar },
    { "nested-externs", &warn_nested_externs },
    { "nonnull", &warn_nonnull },
    { "parentheses", &warn_parentheses },
    { "pointer-arith", &warn_pointer_arith },
    { "redundant-decls", &warn_redundant_decls },
    { "return-type", &warn_return_type },
    { "sequence-point", &warn_sequence_point },
    { "sign-compare", &warn_sign_compare },
    { "strict-prototypes", &warn_strict_prototypes },
    { "traditional", &warn_traditional },
    { "trigraphs", NULL },
    { "undef", NULL },
    { "write-strings", &flag_const_strings }
  };

  strings_processed = cpp_handle_option (parse_in, argc, argv, 0);

  if (!strcmp (p, "-fhosted") || !strcmp (p, "-fno-freestanding"))
    {
      flag_hosted = 1;
      flag_no_builtin = 0;
    }
  else if (!strcmp (p, "-ffreestanding") || !strcmp (p, "-fno-hosted"))
    {
      flag_hosted = 0;
      flag_no_builtin = 1;
      /* warn_main will be 2 if set by -Wall, 1 if set by -Wmain */
      if (warn_main == 2)
	warn_main = 0;
    }
  else if (!strncmp (p, "-std=", 5))
    {
      /* Select the appropriate language standard.  We currently
	 recognize:
	 -std=iso9899:1990	same as -ansi
	 -std=iso9899:199409	ISO C as modified in amend. 1
	 -std=iso9899:1999	ISO C 99
	 -std=c89		same as -std=iso9899:1990
	 -std=c99		same as -std=iso9899:1999
	 -std=gnu89		default, iso9899:1990 + gnu extensions
	 -std=gnu99		iso9899:1999 + gnu extensions
      */
      const char *const argstart = &p[5];

      if (!strcmp (argstart, "iso9899:1990")
	  || !strcmp (argstart, "c89"))
	{
	iso_1990:
	  flag_isoc94 = 0;
	iso_1994:
	  flag_writable_strings = 0;
	  flag_no_asm = 1;
	  flag_no_nonansi_builtin = 1;
	  flag_noniso_default_format_attributes = 0;
	  flag_isoc99 = 0;
	  flag_iso = 1;
	}
      else if (!strcmp (argstart, "iso9899:199409"))
	{
	  flag_isoc94 = 1;
	  goto iso_1994;
	}
      else if (!strcmp (argstart, "iso9899:199x")
	       || !strcmp (argstart, "iso9899:1999")
	       || !strcmp (argstart, "c9x")
	       || !strcmp (argstart, "c99"))
	{
	  flag_writable_strings = 0;
	  flag_no_asm = 1;
	  flag_no_nonansi_builtin = 1;
	  flag_noniso_default_format_attributes = 0;
	  flag_isoc99 = 1;
	  flag_isoc94 = 1;
	  flag_iso = 1;
	}
      else if (!strcmp (argstart, "gnu89"))
	{
	  flag_writable_strings = 0;
	  flag_no_asm = 0;
	  flag_no_nonansi_builtin = 0;
	  flag_noniso_default_format_attributes = 1;
	  flag_isoc99 = 0;
	  flag_isoc94 = 0;
	}
      else if (!strcmp (argstart, "gnu9x") || !strcmp (argstart, "gnu99"))
	{
	  flag_writable_strings = 0;
	  flag_no_asm = 0;
	  flag_no_nonansi_builtin = 0;
	  flag_noniso_default_format_attributes = 1;
	  flag_isoc99 = 1;
	  flag_isoc94 = 1;
	}
      else if (!strcmp (argstart, "c++98"))
	; /* Handled by cpplib.  */
      else
	error ("unknown C standard `%s'", argstart);
    }
  else if (!strcmp (p, "-fdollars-in-identifiers"))
    dollars_in_ident = 1;
  else if (!strcmp (p, "-fno-dollars-in-identifiers"))
    dollars_in_ident = 0;
  else if (!strcmp (p, "-fsigned-char"))
    flag_signed_char = 1;
  else if (!strcmp (p, "-funsigned-char"))
    flag_signed_char = 0;
  else if (!strcmp (p, "-fno-signed-char"))
    flag_signed_char = 0;
  else if (!strcmp (p, "-fno-unsigned-char"))
    flag_signed_char = 1;
  else if (!strcmp (p, "-fsigned-bitfields")
	   || !strcmp (p, "-fno-unsigned-bitfields"))
    {
      flag_signed_bitfields = 1;
      explicit_flag_signed_bitfields = 1;
    }
  else if (!strcmp (p, "-funsigned-bitfields")
	   || !strcmp (p, "-fno-signed-bitfields"))
    {
      flag_signed_bitfields = 0;
      explicit_flag_signed_bitfields = 1;
    }
  else if (!strcmp (p, "-fshort-enums"))
    flag_short_enums = 1;
  else if (!strcmp (p, "-fno-short-enums"))
    flag_short_enums = 0;
  else if (!strcmp (p, "-fshort-wchar"))
    flag_short_wchar = 1;
  else if (!strcmp (p, "-fno-short-wchar"))
    flag_short_wchar = 0;
  else if (!strcmp (p, "-fcond-mismatch"))
    flag_cond_mismatch = 1;
  else if (!strcmp (p, "-fno-cond-mismatch"))
    flag_cond_mismatch = 0;
  else if (!strcmp (p, "-fshort-double"))
    flag_short_double = 1;
  else if (!strcmp (p, "-fno-short-double"))
    flag_short_double = 0;
  else if (!strcmp (p, "-fasm"))
    flag_no_asm = 0;
  else if (!strcmp (p, "-fno-asm"))
    flag_no_asm = 1;
  else if (!strcmp (p, "-fbuiltin"))
    flag_no_builtin = 0;
  else if (!strcmp (p, "-fno-builtin"))
    flag_no_builtin = 1;
  else if (!strncmp (p, "-fno-builtin-", strlen ("-fno-builtin-")))
    disable_builtin_function (p + strlen ("-fno-builtin-"));
  else if (p[0] == '-' && p[1] == 'f' && dump_switch_p (p + 2))
    ;
  else if (!strcmp (p, "-ansi"))
    goto iso_1990;
  else if (!strcmp (p, "-undef"))
    flag_undef = 1;
  else if (!strcmp (p, "-Werror-implicit-function-declaration"))
    mesg_implicit_function_declaration = 2;
  else if (!strncmp (p, "-Wformat=", 9))
    set_Wformat (atoi (p + 9));
  else if (!strcmp (p, "-Wformat"))
    set_Wformat (1);
  else if (!strcmp (p, "-Wno-format"))
    set_Wformat (0);
  else if (!strcmp (p, "-Wimplicit"))
    {
      warn_implicit_int = 1;
      if (mesg_implicit_function_declaration != 2)
	mesg_implicit_function_declaration = 1;
    }
  else if (!strcmp (p, "-Wno-implicit"))
    warn_implicit_int = 0, mesg_implicit_function_declaration = 0;
  else if (!strcmp (p, "-Wno-main"))
    warn_main = -1;
  else if (!strcmp (p, "-Wunknown-pragmas"))
    /* Set to greater than 1, so that even unknown pragmas in system
       headers will be warned about.  */
    warn_unknown_pragmas = 2;
  else if (!strcmp (p, "-Wno-unknown-pragmas"))
    warn_unknown_pragmas = 0;
  else if (!strcmp (p, "-Wall"))
    {
      /* We save the value of warn_uninitialized, since if they put
	 -Wuninitialized on the command line, we need to generate a
	 warning about not using it without also specifying -O.  */
      if (warn_uninitialized != 1)
	warn_uninitialized = 2;
      warn_implicit_int = 1;
      mesg_implicit_function_declaration = 1;
      warn_return_type = 1;
      set_Wunused (1);
      warn_switch = 1;
      set_Wformat (1);
      warn_char_subscripts = 1;
      warn_parentheses = 1;
      warn_sequence_point = 1;
      warn_missing_braces = 1;
      /* We set this to 2 here, but 1 in -Wmain, so -ffreestanding can turn
	 it off only if it's not explicit.  */
      warn_main = 2;
      /* Only warn about unknown pragmas that are not in system headers.  */
      warn_unknown_pragmas = 1;
    }
  else if (!strcmp (p, "-E"))
    flag_preprocess_only = 1;
  else
    {
      size_t i;
      for (i = 0; i < sizeof (warn_options) / sizeof (warn_options[0]); i++)
	if (strncmp (p, "-W", 2) == 0 
	    && warn_options[i].flag
	    && (strcmp (p+2, warn_options[i].option) == 0
		|| (strncmp (p+2, "no-", 3) == 0
		    && strcmp (p+5, warn_options[i].option) == 0)))
	  {
	    *(warn_options[i].flag) = strncmp (p+2, "no-", 3) != 0;
	    return 1;
	  }
      return strings_processed;
    }

  return 1;
}

void
c_print_identifier (file, node, indent)
     FILE *file;
     tree node;
     int indent;
{
  print_node (file, "global", IDENTIFIER_GLOBAL_VALUE (node), indent + 4);
  print_node (file, "local", IDENTIFIER_LOCAL_VALUE (node), indent + 4);
  print_node (file, "label", IDENTIFIER_LABEL_VALUE (node), indent + 4);
  print_node (file, "implicit", IDENTIFIER_IMPLICIT_DECL (node), indent + 4);
  print_node (file, "error locus", IDENTIFIER_ERROR_LOCUS (node), indent + 4);
  print_node (file, "limbo value", IDENTIFIER_LIMBO_VALUE (node), indent + 4);
  if (C_IS_RESERVED_WORD (node))
    {
      tree rid = ridpointers[C_RID_CODE (node)];
      indent_to (file, indent + 4);
      fprintf (file, "rid ");
      fprintf (file, HOST_PTR_PRINTF, (void *)rid);
      fprintf (file, " \"%s\"", IDENTIFIER_POINTER (rid));
    }
}

/* Hook called at end of compilation to assume 1 elt
   for a top-level tentative array defn that wasn't complete before.  */

void
c_finish_incomplete_decl (decl)
     tree decl;
{
  if (TREE_CODE (decl) == VAR_DECL)
    {
      tree type = TREE_TYPE (decl);
      if (type != error_mark_node
	  && TREE_CODE (type) == ARRAY_TYPE
	  && ! DECL_EXTERNAL (decl)
	  && TYPE_DOMAIN (type) == 0)
	{
	  warning_with_decl (decl, "array `%s' assumed to have one element");

	  complete_array_type (type, NULL_TREE, 1);

	  layout_decl (decl, 0);
	}
    }
}

/* Create a new `struct binding_level'.  */

static struct binding_level *
make_binding_level ()
{
  /* NOSTRICT */
  return (struct binding_level *) xmalloc (sizeof (struct binding_level));
}

/* Nonzero if we are currently in the global binding level.  */

int
global_bindings_p ()
{
  return current_binding_level == global_binding_level;
}

void
keep_next_level ()
{
  keep_next_level_flag = 1;
}

/* Nonzero if the current level needs to have a BLOCK made.  */

int
kept_level_p ()
{
  return ((current_binding_level->keep_if_subblocks
	   && current_binding_level->blocks != 0)
	  || current_binding_level->keep
	  || current_binding_level->names != 0
	  || (current_binding_level->tags != 0
	      && !current_binding_level->tag_transparent));
}

/* Identify this binding level as a level of parameters.
   DEFINITION_FLAG is 1 for a definition, 0 for a declaration.
   But it turns out there is no way to pass the right value for
   DEFINITION_FLAG, so we ignore it.  */

void
declare_parm_level (definition_flag)
     int definition_flag ATTRIBUTE_UNUSED;
{
  current_binding_level->parm_flag = 1;
}

/* Nonzero if currently making parm declarations.  */

int
in_parm_level_p ()
{
  return current_binding_level->parm_flag;
}

/* Enter a new binding level.
   If TAG_TRANSPARENT is nonzero, do so only for the name space of variables,
   not for that of tags.  */

void
pushlevel (tag_transparent)
     int tag_transparent;
{
  struct binding_level *newlevel = NULL_BINDING_LEVEL;

  /* If this is the top level of a function,
     just make sure that NAMED_LABELS is 0.  */

  if (current_binding_level == global_binding_level)
    {
      named_labels = 0;
    }

  /* Reuse or create a struct for this binding level.  */

  if (free_binding_level)
    {
      newlevel = free_binding_level;
      free_binding_level = free_binding_level->level_chain;
    }
  else
    {
      newlevel = make_binding_level ();
    }

  /* Add this level to the front of the chain (stack) of levels that
     are active.  */

  *newlevel = clear_binding_level;
  newlevel->tag_transparent
    = (tag_transparent
       || (current_binding_level
	   ? current_binding_level->subblocks_tag_transparent
	   : 0));
  newlevel->level_chain = current_binding_level;
  current_binding_level = newlevel;
  newlevel->keep = keep_next_level_flag;
  keep_next_level_flag = 0;
  newlevel->keep_if_subblocks = keep_next_if_subblocks;
  keep_next_if_subblocks = 0;
}

/* Clear the limbo values of all identifiers defined in BLOCK or a subblock.  */

static void
clear_limbo_values (block)
     tree block;
{
  tree tem;

  for (tem = BLOCK_VARS (block); tem; tem = TREE_CHAIN (tem))
    if (DECL_NAME (tem) != 0)
      IDENTIFIER_LIMBO_VALUE (DECL_NAME (tem)) = 0;

  for (tem = BLOCK_SUBBLOCKS (block); tem; tem = TREE_CHAIN (tem))
    clear_limbo_values (tem);
}

/* Exit a binding level.
   Pop the level off, and restore the state of the identifier-decl mappings
   that were in effect when this level was entered.

   If KEEP is nonzero, this level had explicit declarations, so
   and create a "block" (a BLOCK node) for the level
   to record its declarations and subblocks for symbol table output.

   If FUNCTIONBODY is nonzero, this level is the body of a function,
   so create a block as if KEEP were set and also clear out all
   label names.

   If REVERSE is nonzero, reverse the order of decls before putting
   them into the BLOCK.  */

tree
poplevel (keep, reverse, functionbody)
     int keep;
     int reverse;
     int functionbody;
{
  tree link;
  /* The chain of decls was accumulated in reverse order.
     Put it into forward order, just for cleanliness.  */
  tree decls;
  tree tags = current_binding_level->tags;
  tree subblocks = current_binding_level->blocks;
  tree block = 0;
  tree decl;
  int block_previously_created;

  keep |= current_binding_level->keep;

  /* This warning is turned off because it causes warnings for
     declarations like `extern struct foo *x'.  */
#if 0
  /* Warn about incomplete structure types in this level.  */
  for (link = tags; link; link = TREE_CHAIN (link))
    if (!COMPLETE_TYPE_P (TREE_VALUE (link)))
      {
	tree type = TREE_VALUE (link);
	tree type_name = TYPE_NAME (type);
	char *id = IDENTIFIER_POINTER (TREE_CODE (type_name) == IDENTIFIER_NODE
				       ? type_name
				       : DECL_NAME (type_name));
	switch (TREE_CODE (type))
	  {
	  case RECORD_TYPE:
	    error ("`struct %s' incomplete in scope ending here", id);
	    break;
	  case UNION_TYPE:
	    error ("`union %s' incomplete in scope ending here", id);
	    break;
	  case ENUMERAL_TYPE:
	    error ("`enum %s' incomplete in scope ending here", id);
	    break;
	  }
      }
#endif /* 0 */

  /* Get the decls in the order they were written.
     Usually current_binding_level->names is in reverse order.
     But parameter decls were previously put in forward order.  */

  if (reverse)
    current_binding_level->names
      = decls = nreverse (current_binding_level->names);
  else
    decls = current_binding_level->names;

  /* Output any nested inline functions within this block
     if they weren't already output.  */

  for (decl = decls; decl; decl = TREE_CHAIN (decl))
    if (TREE_CODE (decl) == FUNCTION_DECL
	&& ! TREE_ASM_WRITTEN (decl)
	&& DECL_INITIAL (decl) != 0
	&& TREE_ADDRESSABLE (decl))
      {
	/* If this decl was copied from a file-scope decl
	   on account of a block-scope extern decl,
	   propagate TREE_ADDRESSABLE to the file-scope decl.

	   DECL_ABSTRACT_ORIGIN can be set to itself if warn_return_type is
	   true, since then the decl goes through save_for_inline_copying.  */
	if (DECL_ABSTRACT_ORIGIN (decl) != 0
	    && DECL_ABSTRACT_ORIGIN (decl) != decl)
	  TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (decl)) = 1;
      }

  /* We used to warn about unused variables in expand_end_bindings,
     i.e. while generating RTL.  But in function-at-a-time mode we may
     choose to never expand a function at all (e.g. auto inlining), so
     we do this explicitly now.  */
  warn_about_unused_variables (getdecls ());

  /* If there were any declarations or structure tags in that level,
     or if this level is a function body,
     create a BLOCK to record them for the life of this function.  */

  block = 0;
  block_previously_created = (current_binding_level->this_block != 0);
  if (block_previously_created)
    block = current_binding_level->this_block;
  else if (keep || functionbody
	   || (current_binding_level->keep_if_subblocks && subblocks != 0))
    block = make_node (BLOCK);
  if (block != 0)
    {
      BLOCK_VARS (block) = decls;
      BLOCK_SUBBLOCKS (block) = subblocks;
    }

  /* In each subblock, record that this is its superior.  */

  for (link = subblocks; link; link = TREE_CHAIN (link))
    BLOCK_SUPERCONTEXT (link) = block;

  /* Clear out the meanings of the local variables of this level.  */

  for (link = decls; link; link = TREE_CHAIN (link))
    {
      if (DECL_NAME (link) != 0)
	{
	  /* If the ident. was used or addressed via a local extern decl,
	     don't forget that fact.  */
	  if (DECL_EXTERNAL (link))
	    {
	      if (TREE_USED (link))
		TREE_USED (DECL_NAME (link)) = 1;
	      if (TREE_ADDRESSABLE (link))
		TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (link)) = 1;
	    }
	  IDENTIFIER_LOCAL_VALUE (DECL_NAME (link)) = 0;
	}
    }

  /* Restore all name-meanings of the outer levels
     that were shadowed by this level.  */

  for (link = current_binding_level->shadowed; link; link = TREE_CHAIN (link))
    IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);

  /* If the level being exited is the top level of a function,
     check over all the labels, and clear out the current
     (function local) meanings of their names.  */

  if (functionbody)
    {
      clear_limbo_values (block);

      /* If this is the top level block of a function,
	 the vars are the function's parameters.
	 Don't leave them in the BLOCK because they are
	 found in the FUNCTION_DECL instead.  */

      BLOCK_VARS (block) = 0;

      /* Clear out the definitions of all label names,
	 since their scopes end here,
	 and add them to BLOCK_VARS.  */

      for (link = named_labels; link; link = TREE_CHAIN (link))
	{
	  tree label = TREE_VALUE (link);

	  if (DECL_INITIAL (label) == 0)
	    {
	      error_with_decl (label, "label `%s' used but not defined");
	      /* Avoid crashing later.  */
	      define_label (input_filename, lineno,
			    DECL_NAME (label));
	    }
	  else if (warn_unused_label && !TREE_USED (label))
	    warning_with_decl (label, "label `%s' defined but not used");
	  IDENTIFIER_LABEL_VALUE (DECL_NAME (label)) = 0;

	  /* Put the labels into the "variables" of the
	     top-level block, so debugger can see them.  */
	  TREE_CHAIN (label) = BLOCK_VARS (block);
	  BLOCK_VARS (block) = label;
	}
    }

  /* Pop the current level, and free the structure for reuse.  */

  {
    struct binding_level *level = current_binding_level;
    current_binding_level = current_binding_level->level_chain;

    level->level_chain = free_binding_level;
    free_binding_level = level;
  }

  /* Dispose of the block that we just made inside some higher level.  */
  if (functionbody)
    DECL_INITIAL (current_function_decl) = block;
  else if (block)
    {
      if (!block_previously_created)
	current_binding_level->blocks
	  = chainon (current_binding_level->blocks, block);
    }
  /* If we did not make a block for the level just exited,
     any blocks made for inner levels
     (since they cannot be recorded as subblocks in that level)
     must be carried forward so they will later become subblocks
     of something else.  */
  else if (subblocks)
    current_binding_level->blocks
      = chainon (current_binding_level->blocks, subblocks);

  /* Set the TYPE_CONTEXTs for all of the tagged types belonging to this
     binding contour so that they point to the appropriate construct, i.e.
     either to the current FUNCTION_DECL node, or else to the BLOCK node
     we just constructed.

     Note that for tagged types whose scope is just the formal parameter
     list for some function type specification, we can't properly set
     their TYPE_CONTEXTs here, because we don't have a pointer to the
     appropriate FUNCTION_TYPE node readily available to us.  For those
     cases, the TYPE_CONTEXTs of the relevant tagged type nodes get set
     in `grokdeclarator' as soon as we have created the FUNCTION_TYPE
     node which will represent the "scope" for these "parameter list local"
     tagged types.  */

  if (functionbody)
    for (link = tags; link; link = TREE_CHAIN (link))
      TYPE_CONTEXT (TREE_VALUE (link)) = current_function_decl;
  else if (block)
    for (link = tags; link; link = TREE_CHAIN (link))
      TYPE_CONTEXT (TREE_VALUE (link)) = block;

  if (block)
    TREE_USED (block) = 1;

  return block;
}

/* Insert BLOCK at the end of the list of subblocks of the
   current binding level.  This is used when a BIND_EXPR is expanded,
   to handle the BLOCK node inside the BIND_EXPR.  */

void
insert_block (block)
     tree block;
{
  TREE_USED (block) = 1;
  current_binding_level->blocks
    = chainon (current_binding_level->blocks, block);
}

/* Set the BLOCK node for the innermost scope
   (the one we are currently in).  */

void
set_block (block)
     tree block;
{
  current_binding_level->this_block = block;
  current_binding_level->names = chainon (current_binding_level->names,
					  BLOCK_VARS (block));
  current_binding_level->blocks = chainon (current_binding_level->blocks,
					   BLOCK_SUBBLOCKS (block));
}

void
push_label_level ()
{
  struct binding_level *newlevel;

  /* Reuse or create a struct for this binding level.  */

  if (free_binding_level)
    {
      newlevel = free_binding_level;
      free_binding_level = free_binding_level->level_chain;
    }
  else
    {
      newlevel = make_binding_level ();
    }

  /* Add this level to the front of the chain (stack) of label levels.  */

  newlevel->level_chain = label_level_chain;
  label_level_chain = newlevel;

  newlevel->names = named_labels;
  newlevel->shadowed = shadowed_labels;
  named_labels = 0;
  shadowed_labels = 0;
}

void
pop_label_level ()
{
  struct binding_level *level = label_level_chain;
  tree link, prev;

  /* Clear out the definitions of the declared labels in this level.
     Leave in the list any ordinary, non-declared labels.  */
  for (link = named_labels, prev = 0; link;)
    {
      if (C_DECLARED_LABEL_FLAG (TREE_VALUE (link)))
	{
	  if (DECL_SOURCE_LINE (TREE_VALUE (link)) == 0)
	    {
	      error_with_decl (TREE_VALUE (link),
			       "label `%s' used but not defined");
	      /* Avoid crashing later.  */
	      define_label (input_filename, lineno,
			    DECL_NAME (TREE_VALUE (link)));
	    }
	  else if (warn_unused_label && !TREE_USED (TREE_VALUE (link)))
	    warning_with_decl (TREE_VALUE (link),
			       "label `%s' defined but not used");
	  IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link))) = 0;

	  /* Delete this element from the list.  */
	  link = TREE_CHAIN (link);
	  if (prev)
	    TREE_CHAIN (prev) = link;
	  else
	    named_labels = link;
	}
      else
	{
	  prev = link;
	  link = TREE_CHAIN (link);
	}
    }

  /* Bring back all the labels that were shadowed.  */
  for (link = shadowed_labels; link; link = TREE_CHAIN (link))
    if (DECL_NAME (TREE_VALUE (link)) != 0)
      IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
	= TREE_VALUE (link);

  named_labels = chainon (named_labels, level->names);
  shadowed_labels = level->shadowed;

  /* Pop the current level, and free the structure for reuse.  */
  label_level_chain = label_level_chain->level_chain;
  level->level_chain = free_binding_level;
  free_binding_level = level;
}

/* Push a definition or a declaration of struct, union or enum tag "name".
   "type" should be the type node.
   We assume that the tag "name" is not already defined.

   Note that the definition may really be just a forward reference.
   In that case, the TYPE_SIZE will be zero.  */

void
pushtag (name, type)
     tree name, type;
{
  struct binding_level *b;

  /* Find the proper binding level for this type tag.  */

  for (b = current_binding_level; b->tag_transparent; b = b->level_chain)
    continue;

  if (name)
    {
      /* Record the identifier as the type's name if it has none.  */

      if (TYPE_NAME (type) == 0)
	TYPE_NAME (type) = name;
    }

  b->tags = tree_cons (name, type, b->tags);

  /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
     tagged type we just added to the current binding level.  This fake
     NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
     to output a representation of a tagged type, and it also gives
     us a convenient place to record the "scope start" address for the
     tagged type.  */

  TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));

  /* An approximation for now, so we can tell this is a function-scope tag.
     This will be updated in poplevel.  */
  TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
}

/* Handle when a new declaration NEWDECL
   has the same name as an old one OLDDECL
   in the same binding contour.
   Prints an error message if appropriate.

   If safely possible, alter OLDDECL to look like NEWDECL, and return 1.
   Otherwise, return 0.

   When DIFFERENT_BINDING_LEVEL is true, NEWDECL is an external declaration,
   and OLDDECL is in an outer binding level and should thus not be changed.  */

static int
duplicate_decls (newdecl, olddecl, different_binding_level)
     tree newdecl, olddecl;
     int different_binding_level;
{
  int types_match = comptypes (TREE_TYPE (newdecl), TREE_TYPE (olddecl));
  int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
			   && DECL_INITIAL (newdecl) != 0);
  tree oldtype = TREE_TYPE (olddecl);
  tree newtype = TREE_TYPE (newdecl);
  int errmsg = 0;

  if (DECL_P (olddecl))
    {
      if (TREE_CODE (newdecl) == FUNCTION_DECL
	  && TREE_CODE (olddecl) == FUNCTION_DECL
	  && (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl)))
	{
	  if (DECL_DECLARED_INLINE_P (newdecl)
	      && DECL_UNINLINABLE (newdecl)
	      && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
	    /* Already warned elsewhere.  */;
	  else if (DECL_DECLARED_INLINE_P (olddecl)
		   && DECL_UNINLINABLE (olddecl)
		   && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
	    /* Already warned.  */;
	  else if (DECL_DECLARED_INLINE_P (newdecl)
		   && ! DECL_DECLARED_INLINE_P (olddecl)
		   && DECL_UNINLINABLE (olddecl)
		   && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
	    {
	      warning_with_decl (newdecl,
				 "function `%s' redeclared as inline");
	      warning_with_decl (olddecl,
				 "previous declaration of function `%s' with attribute noinline");
	    }
	  else if (DECL_DECLARED_INLINE_P (olddecl)
		   && DECL_UNINLINABLE (newdecl)
		   && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
	    {
	      warning_with_decl (newdecl,
				 "function `%s' redeclared with attribute noinline");
	      warning_with_decl (olddecl,
				 "previous declaration of function `%s' was inline");
	    }
	}

      DECL_ATTRIBUTES (newdecl)
	= (*targetm.merge_decl_attributes) (olddecl, newdecl);
    }

  if (TREE_CODE (newtype) == ERROR_MARK
      || TREE_CODE (oldtype) == ERROR_MARK)
    types_match = 0;

  /* New decl is completely inconsistent with the old one =>
     tell caller to replace the old one.
     This is always an error except in the case of shadowing a builtin.  */
  if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
    {
      if (TREE_CODE (olddecl) == FUNCTION_DECL
	  && (DECL_BUILT_IN (olddecl)
	      || DECL_BUILT_IN_NONANSI (olddecl)))
	{
	  /* If you declare a built-in or predefined function name as static,
	     the old definition is overridden,
	     but optionally warn this was a bad choice of name.  */
	  if (!TREE_PUBLIC (newdecl))
	    {
	      if (!warn_shadow)
		;
	      else if (DECL_BUILT_IN (olddecl))
		warning_with_decl (newdecl, "shadowing built-in function `%s'");
	      else
		warning_with_decl (newdecl, "shadowing library function `%s'");
	    }
	  /* Likewise, if the built-in is not ansi, then programs can
	     override it even globally without an error.  */
	  else if (! DECL_BUILT_IN (olddecl))
	    warning_with_decl (newdecl,
			       "library function `%s' declared as non-function");

	  else if (DECL_BUILT_IN_NONANSI (olddecl))
	    warning_with_decl (newdecl,
			       "built-in function `%s' declared as non-function");
	  else
	    warning_with_decl (newdecl,
			       "built-in function `%s' declared as non-function");
	}
      else
	{
	  error_with_decl (newdecl, "`%s' redeclared as different kind of symbol");
	  error_with_decl (olddecl, "previous declaration of `%s'");
	}

      return 0;
    }

  /* For real parm decl following a forward decl,
     return 1 so old decl will be reused.  */
  if (types_match && TREE_CODE (newdecl) == PARM_DECL
      && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
    return 1;

  /* The new declaration is the same kind of object as the old one.
     The declarations may partially match.  Print warnings if they don't
     match enough.  Ultimately, copy most of the information from the new
     decl to the old one, and keep using the old one.  */

  if (TREE_CODE (olddecl) == FUNCTION_DECL && DECL_BUILT_IN (olddecl))
    {
      /* A function declaration for a built-in function.  */
      if (!TREE_PUBLIC (newdecl))
	{
	  /* If you declare a built-in function name as static, the
	     built-in definition is overridden,
	     but optionally warn this was a bad choice of name.  */
	  if (warn_shadow)
	    warning_with_decl (newdecl, "shadowing built-in function `%s'");
	  /* Discard the old built-in function.  */
	  return 0;
	}
      else if (!types_match)
	{
	  /* Accept the return type of the new declaration if same modes.  */
	  tree oldreturntype = TREE_TYPE (oldtype);
	  tree newreturntype = TREE_TYPE (newtype);

	  if (TYPE_MODE (oldreturntype) == TYPE_MODE (newreturntype))
	    {
	      /* Function types may be shared, so we can't just modify
		 the return type of olddecl's function type.  */
	      tree trytype
		= build_function_type (newreturntype,
				       TYPE_ARG_TYPES (oldtype));
	      trytype = build_type_attribute_variant (trytype,
						      TYPE_ATTRIBUTES (oldtype));

              types_match = comptypes (newtype, trytype);
	      if (types_match)
		oldtype = trytype;
	    }
	  /* Accept harmless mismatch in first argument type also.
	     This is for the ffs and fprintf builtins.  */
	  if (TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0
	      && TYPE_ARG_TYPES (oldtype) != 0
	      && TREE_VALUE (TYPE_ARG_TYPES (newtype)) != 0
	      && TREE_VALUE (TYPE_ARG_TYPES (oldtype)) != 0
	      && (TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (newtype)))
		  == TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (oldtype)))))
	    {
	      /* Function types may be shared, so we can't just modify
		 the return type of olddecl's function type.  */
	      tree trytype
		= build_function_type (TREE_TYPE (oldtype),
				       tree_cons (NULL_TREE,
						  TREE_VALUE (TYPE_ARG_TYPES (newtype)),
						  TREE_CHAIN (TYPE_ARG_TYPES (oldtype))));
	      trytype = build_type_attribute_variant (trytype,
						      TYPE_ATTRIBUTES (oldtype));

	      types_match = comptypes (newtype, trytype);
	      if (types_match)
		oldtype = trytype;
	    }
	  if (! different_binding_level)
	    TREE_TYPE (olddecl) = oldtype;
	}
      else if (TYPE_ARG_TYPES (oldtype) == NULL
	       && TYPE_ARG_TYPES (newtype) != NULL)
	{
	  /* For bcmp, bzero, fputs the builtin type has arguments not
	     specified.  Use the ones from the prototype so that type checking
	     is done for them.  */
	  tree trytype
	    = build_function_type (TREE_TYPE (oldtype),
				   TYPE_ARG_TYPES (newtype));
	  trytype = build_type_attribute_variant (trytype,
						  TYPE_ATTRIBUTES (oldtype));

	  oldtype = trytype;
	  if (! different_binding_level)
	    TREE_TYPE (olddecl) = oldtype;
	}
      if (!types_match)
	{
	  /* If types don't match for a built-in, throw away the built-in.  */
	  warning_with_decl (newdecl, "conflicting types for built-in function `%s'");
	  return 0;
	}
    }
  else if (TREE_CODE (olddecl) == FUNCTION_DECL
	   && DECL_SOURCE_LINE (olddecl) == 0)
    {
      /* A function declaration for a predeclared function
	 that isn't actually built in.  */
      if (!TREE_PUBLIC (newdecl))
	{
	  /* If you declare it as static, the
	     default definition is overridden.  */
	  return 0;
	}
      else if (!types_match)
	{
	  /* If the types don't match, preserve volatility indication.
	     Later on, we will discard everything else about the
	     default declaration.  */
	  TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
	}
    }
  /* Permit char *foo () to match void *foo (...) if not pedantic,
     if one of them came from a system header file.  */
  else if (!types_match
	   && TREE_CODE (olddecl) == FUNCTION_DECL
	   && TREE_CODE (newdecl) == FUNCTION_DECL
	   && TREE_CODE (TREE_TYPE (oldtype)) == POINTER_TYPE
	   && TREE_CODE (TREE_TYPE (newtype)) == POINTER_TYPE
	   && (DECL_IN_SYSTEM_HEADER (olddecl)
	       || DECL_IN_SYSTEM_HEADER (newdecl))
	   && ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (newtype))) == void_type_node
		&& TYPE_ARG_TYPES (oldtype) == 0
		&& self_promoting_args_p (TYPE_ARG_TYPES (newtype))
		&& TREE_TYPE (TREE_TYPE (oldtype)) == char_type_node)
	       ||
	       (TREE_TYPE (TREE_TYPE (newtype)) == char_type_node
		&& TYPE_ARG_TYPES (newtype) == 0
		&& self_promoting_args_p (TYPE_ARG_TYPES (oldtype))
		&& TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)))
    {
      if (pedantic)
	pedwarn_with_decl (newdecl, "conflicting types for `%s'");
      /* Make sure we keep void * as ret type, not char *.  */
      if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)
	TREE_TYPE (newdecl) = newtype = oldtype;

      /* Set DECL_IN_SYSTEM_HEADER, so that if we see another declaration
	 we will come back here again.  */
      DECL_IN_SYSTEM_HEADER (newdecl) = 1;
    }
  else if (!types_match
	   /* Permit char *foo (int, ...); followed by char *foo ();
	      if not pedantic.  */
	   && ! (TREE_CODE (olddecl) == FUNCTION_DECL
		 && ! pedantic
		 /* Return types must still match.  */
		 && comptypes (TREE_TYPE (oldtype),
			       TREE_TYPE (newtype))
		 && TYPE_ARG_TYPES (newtype) == 0))
    {
      error_with_decl (newdecl, "conflicting types for `%s'");
      /* Check for function type mismatch
	 involving an empty arglist vs a nonempty one.  */
      if (TREE_CODE (olddecl) == FUNCTION_DECL
	  && comptypes (TREE_TYPE (oldtype),
			TREE_TYPE (newtype))
	  && ((TYPE_ARG_TYPES (oldtype) == 0
	       && DECL_INITIAL (olddecl) == 0)
	      ||
	      (TYPE_ARG_TYPES (newtype) == 0
	       && DECL_INITIAL (newdecl) == 0)))
	{
	  /* Classify the problem further.  */
	  tree t = TYPE_ARG_TYPES (oldtype);
	  if (t == 0)
	    t = TYPE_ARG_TYPES (newtype);
	  for (; t; t = TREE_CHAIN (t))
	    {
	      tree type = TREE_VALUE (t);

	      if (TREE_CHAIN (t) == 0
		  && TYPE_MAIN_VARIANT (type) != void_type_node)
		{
		  error ("a parameter list with an ellipsis can't match an empty parameter name list declaration");
		  break;
		}

	      if (c_type_promotes_to (type) != type)
		{
		  error ("an argument type that has a default promotion can't match an empty parameter name list declaration");
		  break;
		}
	    }
	}
      error_with_decl (olddecl, "previous declaration of `%s'");
    }
  else
    {
      errmsg = redeclaration_error_message (newdecl, olddecl);
      if (errmsg)
	{
	  switch (errmsg)
	    {
	    case 1:
	      error_with_decl (newdecl, "redefinition of `%s'");
	      break;
	    case 2:
	      error_with_decl (newdecl, "redeclaration of `%s'");
	      break;
	    case 3:
	      error_with_decl (newdecl, "conflicting declarations of `%s'");
	      break;
	    default:
	      abort ();
	    }

	  error_with_decl (olddecl,
			   ((DECL_INITIAL (olddecl)
			     && current_binding_level == global_binding_level)
			    ? "`%s' previously defined here"
			    : "`%s' previously declared here"));
	  return 0;
	}
      else if (TREE_CODE (newdecl) == TYPE_DECL
               && (DECL_IN_SYSTEM_HEADER (olddecl)
                   || DECL_IN_SYSTEM_HEADER (newdecl)))
	{
	  warning_with_decl (newdecl, "redefinition of `%s'");
	  warning_with_decl
	    (olddecl,
	     ((DECL_INITIAL (olddecl)
	       && current_binding_level == global_binding_level)
	      ? "`%s' previously defined here"
	      : "`%s' previously declared here"));
	}
      else if (TREE_CODE (olddecl) == FUNCTION_DECL
	       && DECL_INITIAL (olddecl) != 0
	       && TYPE_ARG_TYPES (oldtype) == 0
	       && TYPE_ARG_TYPES (newtype) != 0
	       && TYPE_ACTUAL_ARG_TYPES (oldtype) != 0)
	{
	  tree type, parm;
	  int nargs;
	  /* Prototype decl follows defn w/o prototype.  */

	  for (parm = TYPE_ACTUAL_ARG_TYPES (oldtype),
	       type = TYPE_ARG_TYPES (newtype),
	       nargs = 1;
	       ;
	       parm = TREE_CHAIN (parm), type = TREE_CHAIN (type), nargs++)
	    {
	      if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
		  && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
		{
		  warning_with_decl (newdecl, "prototype for `%s' follows");
		  warning_with_decl (olddecl, "non-prototype definition here");
		  break;
		}
	      if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
		  || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
		{
		  error_with_decl (newdecl,
				   "prototype for `%s' follows and number of arguments doesn't match");
		  error_with_decl (olddecl, "non-prototype definition here");
		  errmsg = 1;
		  break;
		}
	      /* Type for passing arg must be consistent
		 with that declared for the arg.  */
	      if (! comptypes (TREE_VALUE (parm), TREE_VALUE (type)))
		{
		  error_with_decl (newdecl,
				   "prototype for `%s' follows and argument %d doesn't match",
				   nargs);
		  error_with_decl (olddecl, "non-prototype definition here");
		  errmsg = 1;
		  break;
		}
	    }
	}
      /* Warn about mismatches in various flags.  */
      else
	{
	  /* Warn if function is now inline
	     but was previously declared not inline and has been called.  */
	  if (TREE_CODE (olddecl) == FUNCTION_DECL
	      && ! DECL_DECLARED_INLINE_P (olddecl)
	      && DECL_DECLARED_INLINE_P (newdecl)
	      && TREE_USED (olddecl))
	    warning_with_decl (newdecl,
			       "`%s' declared inline after being called");
	  if (TREE_CODE (olddecl) == FUNCTION_DECL
	      && ! DECL_DECLARED_INLINE_P (olddecl)
	      && DECL_DECLARED_INLINE_P (newdecl)
	      && DECL_INITIAL (olddecl) != 0)
	    warning_with_decl (newdecl,
			       "`%s' declared inline after its definition");

	  /* If pedantic, warn when static declaration follows a non-static
	     declaration.  Otherwise, do so only for functions.  */
	  if ((pedantic || TREE_CODE (olddecl) == FUNCTION_DECL)
	      && TREE_PUBLIC (olddecl)
	      && !TREE_PUBLIC (newdecl))
	    warning_with_decl (newdecl, "static declaration for `%s' follows non-static");

	  /* If warn_traditional, warn when a non-static function
	     declaration follows a static one.  */
	  if (warn_traditional && !in_system_header
	      && TREE_CODE (olddecl) == FUNCTION_DECL
	      && !TREE_PUBLIC (olddecl)
	      && TREE_PUBLIC (newdecl))
	    warning_with_decl (newdecl, "non-static declaration for `%s' follows static");

	  /* Warn when const declaration follows a non-const
	     declaration, but not for functions.  */
	  if (TREE_CODE (olddecl) != FUNCTION_DECL
	      && !TREE_READONLY (olddecl)
	      && TREE_READONLY (newdecl))
	    warning_with_decl (newdecl, "const declaration for `%s' follows non-const");
	  /* These bits are logically part of the type, for variables.
	     But not for functions
	     (where qualifiers are not valid ANSI anyway).  */
	  else if (pedantic && TREE_CODE (olddecl) != FUNCTION_DECL
	      && (TREE_READONLY (newdecl) != TREE_READONLY (olddecl)
		  || TREE_THIS_VOLATILE (newdecl) != TREE_THIS_VOLATILE (olddecl)))
	    pedwarn_with_decl (newdecl, "type qualifiers for `%s' conflict with previous decl");
	}
    }

  /* Optionally warn about more than one declaration for the same name.  */
  if (errmsg == 0 && warn_redundant_decls && DECL_SOURCE_LINE (olddecl) != 0
      /* Don't warn about a function declaration
	 followed by a definition.  */
      && !(TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl) != 0
	   && DECL_INITIAL (olddecl) == 0)
      /* Don't warn about extern decl followed by (tentative) definition.  */
      && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl)))
    {
      warning_with_decl (newdecl, "redundant redeclaration of `%s' in same scope");
      warning_with_decl (olddecl, "previous declaration of `%s'");
    }

  /* Copy all the DECL_... slots specified in the new decl
     except for any that we copy here from the old type.

     Past this point, we don't change OLDTYPE and NEWTYPE
     even if we change the types of NEWDECL and OLDDECL.  */

  if (types_match)
    {
      /* When copying info to olddecl, we store into write_olddecl
	 instead.  This allows us to avoid modifying olddecl when
	 different_binding_level is true.  */
      tree write_olddecl = different_binding_level ? newdecl : olddecl;

      /* Merge the data types specified in the two decls.  */
      if (TREE_CODE (newdecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
	{
	  if (different_binding_level)
	    {
	      if (TYPE_ARG_TYPES (oldtype) != 0
		  && TYPE_ARG_TYPES (newtype) == 0)
		TREE_TYPE (newdecl) = common_type (newtype, oldtype);
	      else
		TREE_TYPE (newdecl)
		  = build_type_attribute_variant
		    (newtype,
		     merge_attributes (TYPE_ATTRIBUTES (newtype),
				       TYPE_ATTRIBUTES (oldtype)));
	    }
	  else
	    TREE_TYPE (newdecl)
	      = TREE_TYPE (olddecl)
		= common_type (newtype, oldtype);
	}

      /* Lay the type out, unless already done.  */
      if (oldtype != TREE_TYPE (newdecl))
	{
	  if (TREE_TYPE (newdecl) != error_mark_node)
	    layout_type (TREE_TYPE (newdecl));
	  if (TREE_CODE (newdecl) != FUNCTION_DECL
	      && TREE_CODE (newdecl) != TYPE_DECL
	      && TREE_CODE (newdecl) != CONST_DECL)
	    layout_decl (newdecl, 0);
	}
      else
	{
	  /* Since the type is OLDDECL's, make OLDDECL's size go with.  */
	  DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
	  DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
	  DECL_MODE (newdecl) = DECL_MODE (olddecl);
	  if (TREE_CODE (olddecl) != FUNCTION_DECL)
	    if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
	      {
		DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
		DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
	      }
	}

      /* Keep the old rtl since we can safely use it.  */
      COPY_DECL_RTL (olddecl, newdecl);

      /* Merge the type qualifiers.  */
      if (TREE_CODE (olddecl) == FUNCTION_DECL
	  && DECL_BUILT_IN_NONANSI (olddecl) && TREE_THIS_VOLATILE (olddecl)
	  && ! TREE_THIS_VOLATILE (newdecl))
	TREE_THIS_VOLATILE (write_olddecl) = 0;

      if (TREE_READONLY (newdecl))
	TREE_READONLY (write_olddecl) = 1;

      if (TREE_THIS_VOLATILE (newdecl))
	{
	  TREE_THIS_VOLATILE (write_olddecl) = 1;
	  if (TREE_CODE (newdecl) == VAR_DECL
	      /* If an automatic variable is re-declared in the same
		 function scope, but the old declaration was not
		 volatile, make_var_volatile() would crash because the
		 variable would have been assigned to a pseudo, not a
		 MEM.  Since this duplicate declaration is invalid
		 anyway, we just skip the call.  */
	      && errmsg == 0)
	    make_var_volatile (newdecl);
	}

      /* Keep source location of definition rather than declaration.  */
      /* When called with different_binding_level set, keep the old
	 information so that meaningful diagnostics can be given.  */
      if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0
	  && ! different_binding_level)
	{
	  DECL_SOURCE_LINE (newdecl) = DECL_SOURCE_LINE (olddecl);
	  DECL_SOURCE_FILE (newdecl) = DECL_SOURCE_FILE (olddecl);
	}

      /* Merge the unused-warning information.  */
      if (DECL_IN_SYSTEM_HEADER (olddecl))
	DECL_IN_SYSTEM_HEADER (newdecl) = 1;
      else if (DECL_IN_SYSTEM_HEADER (newdecl))
	DECL_IN_SYSTEM_HEADER (write_olddecl) = 1;

      /* Merge the initialization information.  */
      /* When called with different_binding_level set, don't copy over
	 DECL_INITIAL, so that we don't accidentally change function
	 declarations into function definitions.  */
      if (DECL_INITIAL (newdecl) == 0 && ! different_binding_level)
	DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);

      /* Merge the section attribute.
         We want to issue an error if the sections conflict but that must be
	 done later in decl_attributes since we are called before attributes
	 are assigned.  */
      if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
	DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);

      /* Copy the assembler name.
	 Currently, it can only be defined in the prototype.  */
      COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);

      if (TREE_CODE (newdecl) == FUNCTION_DECL)
	{
	  DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
	  DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
	  DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
	  DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
	    |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
	}
    }
  /* If cannot merge, then use the new type and qualifiers,
     and don't preserve the old rtl.  */
  else if (! different_binding_level)
    {
      TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
      TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
      TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
      TREE_SIDE_EFFECTS (olddecl) = TREE_SIDE_EFFECTS (newdecl);
    }

  /* Merge the storage class information.  */
  merge_weak (newdecl, olddecl);

  /* For functions, static overrides non-static.  */
  if (TREE_CODE (newdecl) == FUNCTION_DECL)
    {
      TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
      /* This is since we don't automatically
	 copy the attributes of NEWDECL into OLDDECL.  */
      /* No need to worry about different_binding_level here because
	 then TREE_PUBLIC (newdecl) was true.  */
      TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
      /* If this clears `static', clear it in the identifier too.  */
      if (! TREE_PUBLIC (olddecl))
	TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
    }
  if (DECL_EXTERNAL (newdecl))
    {
      if (! different_binding_level)
	{
	  /* Don't mess with these flags on local externs; they remain
	     external even if there's a declaration at file scope which
	     isn't.  */
	  TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
	  DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
	}
      /* An extern decl does not override previous storage class.  */
      TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
      if (! DECL_EXTERNAL (newdecl))
	DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
    }
  else
    {
      TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
      TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
    }

  if (TREE_CODE (newdecl) == FUNCTION_DECL)
    {
      /* If we're redefining a function previously defined as extern
	 inline, make sure we emit debug info for the inline before we
	 throw it away, in case it was inlined into a function that hasn't
	 been written out yet.  */
      if (new_is_definition && DECL_INITIAL (olddecl) && TREE_USED (olddecl))
	{
	  (*debug_hooks->outlining_inline_function) (olddecl);

	  /* The new defn must not be inline.  */
	  DECL_INLINE (newdecl) = 0;
	  DECL_UNINLINABLE (newdecl) = 1;
	}
      else
	{
	  /* If either decl says `inline', this fn is inline,
	     unless its definition was passed already.  */
	  if (DECL_DECLARED_INLINE_P (newdecl)
	      || DECL_DECLARED_INLINE_P (olddecl))
	    DECL_DECLARED_INLINE_P (newdecl) = 1;

	  DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
	    = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
	}

      if (DECL_BUILT_IN (olddecl))
	{
	  /* Get rid of any built-in function if new arg types don't match it
	     or if we have a function definition.  */
	  if (! types_match || new_is_definition)
	    {
	      if (! different_binding_level)
		{
		  TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
		  DECL_BUILT_IN_CLASS (olddecl) = NOT_BUILT_IN;
		}
	    }
	  else
	    {
	      /* If redeclaring a builtin function, and not a definition,
		 it stays built in.  */
	      DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
	      DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
	    }
	}

      /* Also preserve various other info from the definition.  */
      if (! new_is_definition)
	{
	  DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
	  /* When called with different_binding_level set, don't copy over
	     DECL_INITIAL, so that we don't accidentally change function
	     declarations into function definitions.  */
	  if (! different_binding_level)
	    DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
	  DECL_SAVED_INSNS (newdecl) = DECL_SAVED_INSNS (olddecl);
	  DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
	  DECL_NUM_STMTS (newdecl) = DECL_NUM_STMTS (olddecl);
	  DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);

	  /* Set DECL_INLINE on the declaration if we've got a body
	     from which to instantiate.  */
	  if (DECL_INLINE (olddecl) && ! DECL_UNINLINABLE (newdecl))
	    {
	      DECL_INLINE (newdecl) = 1;
	      DECL_ABSTRACT_ORIGIN (newdecl)
		= (different_binding_level
		   ? DECL_ORIGIN (olddecl)
		   : DECL_ABSTRACT_ORIGIN (olddecl));
	    }
	}
      else
	{
	  /* If a previous declaration said inline, mark the
	     definition as inlinable.  */
	  if (DECL_DECLARED_INLINE_P (newdecl)
	      && ! DECL_UNINLINABLE (newdecl))
	    DECL_INLINE (newdecl) = 1;
	}
    }
  if (different_binding_level)
    return 0;

  /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
     But preserve OLDDECL's DECL_UID.  */
  {
    unsigned olddecl_uid = DECL_UID (olddecl);

    memcpy ((char *) olddecl + sizeof (struct tree_common),
	    (char *) newdecl + sizeof (struct tree_common),
	    sizeof (struct tree_decl) - sizeof (struct tree_common));
    DECL_UID (olddecl) = olddecl_uid;
  }

  /* NEWDECL contains the merged attribute lists.
     Update OLDDECL to be the same.  */
  DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);

  return 1;
}

/* Check whether decl-node X shadows an existing declaration.
   OLDLOCAL is the old IDENTIFIER_LOCAL_VALUE of the DECL_NAME of X,
   which might be a NULL_TREE.  */
static void
warn_if_shadowing (x, oldlocal)
     tree x, oldlocal;
{
  tree name;

  if (DECL_EXTERNAL (x))
    return;

  name = DECL_NAME (x);

  /* Warn if shadowing an argument at the top level of the body.  */
  if (oldlocal != 0
      /* This warning doesn't apply to the parms of a nested fcn.  */
      && ! current_binding_level->parm_flag
      /* Check that this is one level down from the parms.  */
      && current_binding_level->level_chain->parm_flag
      /* Check that the decl being shadowed
	 comes from the parm level, one level up.  */
      && chain_member (oldlocal, current_binding_level->level_chain->names))
    {
      if (TREE_CODE (oldlocal) == PARM_DECL)
	pedwarn ("declaration of `%s' shadows a parameter",
		 IDENTIFIER_POINTER (name));
      else
	pedwarn ("declaration of `%s' shadows a symbol from the parameter list",
		 IDENTIFIER_POINTER (name));
    }
  /* Maybe warn if shadowing something else.  */
  else if (warn_shadow
	   /* No shadow warnings for internally generated vars.  */
	   && DECL_SOURCE_LINE (x) != 0
	   /* No shadow warnings for vars made for inlining.  */
	   && ! DECL_FROM_INLINE (x))
    {
      if (TREE_CODE (x) == PARM_DECL
	  && current_binding_level->level_chain->parm_flag)
	/* Don't warn about the parm names in function declarator
	   within a function declarator.
	   It would be nice to avoid warning in any function
	   declarator in a declaration, as opposed to a definition,
	   but there is no way to tell it's not a definition.  */
	;
      else if (oldlocal)
	{
	  if (TREE_CODE (oldlocal) == PARM_DECL)
	    shadow_warning ("a parameter", name, oldlocal);
	  else
	    shadow_warning ("a previous local", name, oldlocal);
	}
      else if (IDENTIFIER_GLOBAL_VALUE (name) != 0
	       && IDENTIFIER_GLOBAL_VALUE (name) != error_mark_node)
	shadow_warning ("a global declaration", name,
			IDENTIFIER_GLOBAL_VALUE (name));
    }
}

/* 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).

   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 (x)
     tree x;
{
  tree t;
  tree name = DECL_NAME (x);
  struct binding_level *b = current_binding_level;

  /* Functions need the lang_decl data.  */
  if (TREE_CODE (x) == FUNCTION_DECL && ! DECL_LANG_SPECIFIC (x))
    DECL_LANG_SPECIFIC (x) = (struct lang_decl *)
      ggc_alloc_cleared (sizeof (struct lang_decl));

  DECL_CONTEXT (x) = current_function_decl;
  /* A local extern declaration for a function doesn't constitute nesting.
     A local auto declaration does, since it's a forward decl
     for a nested function coming later.  */
  if ((TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL)
      && DECL_INITIAL (x) == 0 && DECL_EXTERNAL (x))
    DECL_CONTEXT (x) = 0;

  if (name)
    {
      int different_binding_level = 0;

      if (warn_nested_externs
	  && DECL_EXTERNAL (x)
	  && b != global_binding_level
	  && x != IDENTIFIER_IMPLICIT_DECL (name)
	  /* No error messages for __FUNCTION__ and __PRETTY_FUNCTION__.  */
	  && !DECL_IN_SYSTEM_HEADER (x))
	warning ("nested extern declaration of `%s'",
		 IDENTIFIER_POINTER (name));

      t = lookup_name_current_level (name);
      if (! t && DECL_EXTERNAL (x) && TREE_PUBLIC (x))
	{
	  t = IDENTIFIER_GLOBAL_VALUE (name);
	  /* Type decls at global scope don't conflict with externs declared
	     inside lexical blocks.  */
	  if (! t || TREE_CODE (t) == TYPE_DECL)
	    /* If there's no visible global declaration, try for an
               invisible one.  */
	    t = IDENTIFIER_LIMBO_VALUE (name);
	  different_binding_level = 1;
	}
      if (t != 0 && t == error_mark_node)
	/* error_mark_node is 0 for a while during initialization!  */
	{
	  t = 0;
	  error_with_decl (x, "`%s' used prior to declaration");
	}

      /* If this decl is `static' and an implicit decl was seen previously,
	 warn.  */
      if (TREE_PUBLIC (name)
	  /* Don't test for DECL_EXTERNAL, because grokdeclarator
	     sets this for all functions.  */
	  && ! TREE_PUBLIC (x)
	  && (TREE_CODE (x) == FUNCTION_DECL || b == global_binding_level)
	  /* We used to warn also for explicit extern followed by static,
	     but sometimes you need to do it that way.  */
	  && IDENTIFIER_IMPLICIT_DECL (name) != 0)
	{
	  pedwarn ("`%s' was declared implicitly `extern' and later `static'",
		   IDENTIFIER_POINTER (name));
	  pedwarn_with_file_and_line
	    (DECL_SOURCE_FILE (IDENTIFIER_IMPLICIT_DECL (name)),
	     DECL_SOURCE_LINE (IDENTIFIER_IMPLICIT_DECL (name)),
	     "previous declaration of `%s'",
	     IDENTIFIER_POINTER (name));
	  TREE_THIS_VOLATILE (name) = 1;
	}

      if (t != 0 && duplicate_decls (x, t, different_binding_level))
	{
	  if (TREE_CODE (t) == PARM_DECL)
	    {
	      /* Don't allow more than one "real" duplicate
		 of a forward parm decl.  */
	      TREE_ASM_WRITTEN (t) = TREE_ASM_WRITTEN (x);
	      return t;
	    }
	  return t;
	}

      /* If we are processing a typedef statement, generate a whole new
	 ..._TYPE node (which will be just an variant of the existing
	 ..._TYPE node with identical properties) and then install the
	 TYPE_DECL node generated to represent the typedef name as the
	 TYPE_NAME of this brand new (duplicate) ..._TYPE node.

	 The whole point here is to end up with a situation where each
	 and every ..._TYPE node the compiler creates will be uniquely
	 associated with AT MOST one node representing a typedef name.
	 This way, even though the compiler substitutes corresponding
	 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
	 early on, later parts of the compiler can always do the reverse
	 translation and get back the corresponding typedef name.  For
	 example, given:

		typedef struct S MY_TYPE;
		MY_TYPE object;

	 Later parts of the compiler might only know that `object' was of
	 type `struct S' if it were not for code just below.  With this
	 code however, later parts of the compiler see something like:

		struct S' == struct S
		typedef struct S' MY_TYPE;
		struct S' object;

	 And they can then deduce (from the node for type struct S') that
	 the original object declaration was:

		MY_TYPE object;

	 Being able to do this is important for proper support of protoize,
	 and also for generating precise symbolic debugging information
	 which takes full account of the programmer's (typedef) vocabulary.

         Obviously, we don't want to generate a duplicate ..._TYPE node if
	 the TYPE_DECL node that we are now processing really represents a
	 standard built-in type.

         Since all standard types are effectively declared at line zero
         in the source file, we can easily check to see if we are working
         on a standard type by checking the current value of lineno.  */

      if (TREE_CODE (x) == TYPE_DECL)
	{
	  if (DECL_SOURCE_LINE (x) == 0)
	    {
	      if (TYPE_NAME (TREE_TYPE (x)) == 0)
		TYPE_NAME (TREE_TYPE (x)) = x;
	    }
	  else if (TREE_TYPE (x) != error_mark_node
		   && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
	    {
	      tree tt = TREE_TYPE (x);
	      DECL_ORIGINAL_TYPE (x) = tt;
	      tt = build_type_copy (tt);
	      TYPE_NAME (tt) = x;
	      TREE_USED (tt) = TREE_USED (x);
	      TREE_TYPE (x) = tt;
	    }
	}

      /* Multiple external decls of the same identifier ought to match.
	 We get warnings about inline functions where they are defined.
	 Avoid duplicate warnings where they are used.  */
      if (TREE_PUBLIC (x)
	  && ! (TREE_CODE (x) == FUNCTION_DECL && DECL_INLINE (x)))
	{
	  tree decl;

	  if (IDENTIFIER_LIMBO_VALUE (name) != 0)
	    /* Decls in limbo are always extern, so no need to check that.  */
	    decl = IDENTIFIER_LIMBO_VALUE (name);
	  else
	    decl = 0;

	  if (decl && ! comptypes (TREE_TYPE (x), TREE_TYPE (decl))
	      /* If old decl is built-in, we already warned if we should.  */
	      && !DECL_BUILT_IN (decl))
	    {
	      pedwarn_with_decl (x,
				 "type mismatch with previous external decl");
	      pedwarn_with_decl (decl, "previous external decl of `%s'");
	    }
	}

      /* If a function has had an implicit declaration, and then is defined,
	 make sure they are compatible.  */

      if (IDENTIFIER_IMPLICIT_DECL (name) != 0
	  && IDENTIFIER_GLOBAL_VALUE (name) == 0
	  && TREE_CODE (x) == FUNCTION_DECL
	  && ! comptypes (TREE_TYPE (x),
			  TREE_TYPE (IDENTIFIER_IMPLICIT_DECL (name))))
	{
	  warning_with_decl (x, "type mismatch with previous implicit declaration");
	  warning_with_decl (IDENTIFIER_IMPLICIT_DECL (name),
			     "previous implicit declaration of `%s'");
	}

      /* This name is new in its binding level.
	 Install the new declaration and return it.  */
      if (b == global_binding_level)
	{
	  /* Install a global value.  */

	  /* If the first global decl has external linkage,
	     warn if we later see static one.  */
	  if (IDENTIFIER_GLOBAL_VALUE (name) == 0 && TREE_PUBLIC (x))
	    TREE_PUBLIC (name) = 1;

	  IDENTIFIER_GLOBAL_VALUE (name) = x;

	  /* We no longer care about any previous block level declarations.  */
	  IDENTIFIER_LIMBO_VALUE (name) = 0;

	  /* Don't forget if the function was used via an implicit decl.  */
	  if (IDENTIFIER_IMPLICIT_DECL (name)
	      && TREE_USED (IDENTIFIER_IMPLICIT_DECL (name)))
	    TREE_USED (x) = 1, TREE_USED (name) = 1;

	  /* Don't forget if its address was taken in that way.  */
	  if (IDENTIFIER_IMPLICIT_DECL (name)
	      && TREE_ADDRESSABLE (IDENTIFIER_IMPLICIT_DECL (name)))
	    TREE_ADDRESSABLE (x) = 1;

	  /* Warn about mismatches against previous implicit decl.  */
	  if (IDENTIFIER_IMPLICIT_DECL (name) != 0
	      /* If this real decl matches the implicit, don't complain.  */
	      && ! (TREE_CODE (x) == FUNCTION_DECL
		    && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (x)))
			== integer_type_node)))
	    pedwarn ("`%s' was previously implicitly declared to return `int'",
		     IDENTIFIER_POINTER (name));

	  /* If this decl is `static' and an `extern' was seen previously,
	     that is erroneous.  */
	  if (TREE_PUBLIC (name)
	      && ! TREE_PUBLIC (x) && ! DECL_EXTERNAL (x))
	    {
	      /* Okay to redeclare an ANSI built-in as static.  */
	      if (t != 0 && DECL_BUILT_IN (t))
		;
	      /* Okay to declare a non-ANSI built-in as anything.  */
	      else if (t != 0 && DECL_BUILT_IN_NONANSI (t))
		;
	      /* Okay to have global type decl after an earlier extern
		 declaration inside a lexical block.  */
	      else if (TREE_CODE (x) == TYPE_DECL)
		;
	      else if (IDENTIFIER_IMPLICIT_DECL (name))
		{
		  if (! TREE_THIS_VOLATILE (name))
		    pedwarn ("`%s' was declared implicitly `extern' and later `static'",
			     IDENTIFIER_POINTER (name));
		}
	      else
		pedwarn ("`%s' was declared `extern' and later `static'",
			 IDENTIFIER_POINTER (name));
	    }
	}
      else
	{
	  /* Here to install a non-global value.  */
	  tree oldlocal = IDENTIFIER_LOCAL_VALUE (name);
	  tree oldglobal = IDENTIFIER_GLOBAL_VALUE (name);

	  IDENTIFIER_LOCAL_VALUE (name) = x;

	  /* If this is an extern function declaration, see if we
	     have a global definition or declaration for the function.  */
	  if (oldlocal == 0
	      && oldglobal != 0
	      && TREE_CODE (x) == FUNCTION_DECL
	      && TREE_CODE (oldglobal) == FUNCTION_DECL
	      && DECL_EXTERNAL (x)
	      && ! DECL_DECLARED_INLINE_P (x))
	    {
	      /* We have one.  Their types must agree.  */
	      if (! comptypes (TREE_TYPE (x),
			       TREE_TYPE (IDENTIFIER_GLOBAL_VALUE (name))))
		pedwarn_with_decl (x, "extern declaration of `%s' doesn't match global one");
	      else
		{
		  /* Inner extern decl is inline if global one is.
		     Copy enough to really inline it.  */
		  if (DECL_DECLARED_INLINE_P (oldglobal))
		    {
		      DECL_DECLARED_INLINE_P (x)
		        = DECL_DECLARED_INLINE_P (oldglobal);
		      DECL_INLINE (x) = DECL_INLINE (oldglobal);
		      DECL_INITIAL (x) = (current_function_decl == oldglobal
					  ? 0 : DECL_INITIAL (oldglobal));
		      DECL_SAVED_INSNS (x) = DECL_SAVED_INSNS (oldglobal);
		      DECL_NUM_STMTS (x) = DECL_NUM_STMTS (oldglobal);
		      DECL_ARGUMENTS (x) = DECL_ARGUMENTS (oldglobal);
		      DECL_RESULT (x) = DECL_RESULT (oldglobal);
		      TREE_ASM_WRITTEN (x) = TREE_ASM_WRITTEN (oldglobal);
		      DECL_ABSTRACT_ORIGIN (x)
			= DECL_ABSTRACT_ORIGIN (oldglobal);
		    }
		  /* Inner extern decl is built-in if global one is.  */
		  if (DECL_BUILT_IN (oldglobal))
		    {
		      DECL_BUILT_IN_CLASS (x) = DECL_BUILT_IN_CLASS (oldglobal);
		      DECL_FUNCTION_CODE (x) = DECL_FUNCTION_CODE (oldglobal);
		    }
		  /* Keep the arg types from a file-scope fcn defn.  */
		  if (TYPE_ARG_TYPES (TREE_TYPE (oldglobal)) != 0
		      && DECL_INITIAL (oldglobal)
		      && TYPE_ARG_TYPES (TREE_TYPE (x)) == 0)
		    TREE_TYPE (x) = TREE_TYPE (oldglobal);
		}
	    }

#if 0
	  /* This case is probably sometimes the right thing to do.  */
	  /* If we have a local external declaration,
	     then any file-scope declaration should not
	     have been static.  */
	  if (oldlocal == 0 && oldglobal != 0
	      && !TREE_PUBLIC (oldglobal)
	      && DECL_EXTERNAL (x) && TREE_PUBLIC (x))
	    warning ("`%s' locally external but globally static",
		     IDENTIFIER_POINTER (name));
#endif

	  /* 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 == 0
	      && DECL_EXTERNAL (x)
	      && TREE_PUBLIC (x))
	    {
	      if (oldglobal == 0)
		TREE_PUBLIC (name) = 1;

	      /* Save this decl, so that we can do type checking against
		 other decls after it falls out of scope.

		 Only save it once.  This prevents temporary decls created in
		 expand_inline_function from being used here, since this
		 will have been set when the inline function was parsed.
		 It also helps give slightly better warnings.  */
	      if (IDENTIFIER_LIMBO_VALUE (name) == 0)
		IDENTIFIER_LIMBO_VALUE (name) = x;
	    }

	  warn_if_shadowing (x, oldlocal);

	  /* If storing a local value, there may already be one (inherited).
	     If so, record it for restoration when this binding level ends.  */
	  if (oldlocal != 0)
	    b->shadowed = tree_cons (name, oldlocal, b->shadowed);
	}

      /* Keep count of variables in this level with incomplete type.
	 If the input is erroneous, we can have error_mark in the type
	 slot (e.g. "f(void a, ...)") - that doesn't count as an
	 incomplete type.  */
      if (TREE_TYPE (x) != error_mark_node
	  && !COMPLETE_TYPE_P (TREE_TYPE (x)))
	{
	  tree element = TREE_TYPE (x);

	  while (TREE_CODE (element) == ARRAY_TYPE)
	    element = TREE_TYPE (element);
	  if (TREE_CODE (element) == RECORD_TYPE
	      || TREE_CODE (element) == UNION_TYPE)
	    ++b->n_incomplete;
	}
    }

  /* Put decls on list in reverse order.
     We will reverse them later if necessary.  */
  TREE_CHAIN (x) = b->names;
  b->names = x;

  return x;
}

/* Like pushdecl, only it places X in GLOBAL_BINDING_LEVEL, if appropriate.  */

tree
pushdecl_top_level (x)
     tree x;
{
  tree t;
  struct binding_level *b = current_binding_level;

  current_binding_level = global_binding_level;
  t = pushdecl (x);
  current_binding_level = b;
  return t;
}

/* Generate an implicit declaration for identifier FUNCTIONID
   as a function of type int ().  Print a warning if appropriate.  */

tree
implicitly_declare (functionid)
     tree functionid;
{
  tree decl;
  int traditional_warning = 0;
  /* Only one "implicit declaration" warning per identifier.  */
  int implicit_warning;

  /* We used to reuse an old implicit decl here,
     but this loses with inline functions because it can clobber
     the saved decl chains.  */
#if 0
  if (IDENTIFIER_IMPLICIT_DECL (functionid) != 0)
    decl = IDENTIFIER_IMPLICIT_DECL (functionid);
  else
#endif
    decl = build_decl (FUNCTION_DECL, functionid, default_function_type);

  /* Warn of implicit decl following explicit local extern decl.
     This is probably a program designed for traditional C.  */
  if (TREE_PUBLIC (functionid) && IDENTIFIER_GLOBAL_VALUE (functionid) == 0)
    traditional_warning = 1;

  /* Warn once of an implicit declaration.  */
  implicit_warning = (IDENTIFIER_IMPLICIT_DECL (functionid) == 0);

  DECL_EXTERNAL (decl) = 1;
  TREE_PUBLIC (decl) = 1;

  /* Record that we have an implicit decl and this is it.  */
  IDENTIFIER_IMPLICIT_DECL (functionid) = decl;

  /* ANSI standard says implicit declarations are in the innermost block.
     So we record the decl in the standard fashion.  */
  pushdecl (decl);

  /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
  maybe_objc_check_decl (decl);

  rest_of_decl_compilation (decl, NULL, 0, 0);

  if (implicit_warning)
    implicit_decl_warning (functionid);
  else if (warn_traditional && traditional_warning)
    warning ("function `%s' was previously declared within a block",
	     IDENTIFIER_POINTER (functionid));

  /* Write a record describing this implicit function declaration to the
     prototypes file (if requested).  */

  gen_aux_info_record (decl, 0, 1, 0);

  /* Possibly apply some default attributes to this implicit declaration.  */
  decl_attributes (&decl, NULL_TREE, 0);

  return decl;
}

void
implicit_decl_warning (id)
     tree id;
{
  const char *name = IDENTIFIER_POINTER (id);
  if (mesg_implicit_function_declaration == 2)
    error ("implicit declaration of function `%s'", name);
  else if (mesg_implicit_function_declaration == 1)
    warning ("implicit declaration of function `%s'", name);
}

/* Return zero if the declaration NEWDECL is valid
   when the declaration OLDDECL (assumed to be for the same name)
   has already been seen.
   Otherwise return 1 if NEWDECL is a redefinition, 2 if it is a redeclaration,
   and 3 if it is a conflicting declaration.  */

static int
redeclaration_error_message (newdecl, olddecl)
     tree newdecl, olddecl;
{
  if (TREE_CODE (newdecl) == TYPE_DECL)
    {
      /* Do not complain about type redeclarations where at least one
	 declaration was in a system header.  */
      if (DECL_IN_SYSTEM_HEADER (olddecl) || DECL_IN_SYSTEM_HEADER (newdecl))
	return 0;
      return 1;
    }
  else if (TREE_CODE (newdecl) == FUNCTION_DECL)
    {
      /* Declarations of functions can insist on internal linkage
	 but they can't be inconsistent with internal linkage,
	 so there can be no error on that account.
	 However defining the same name twice is no good.  */
      if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0
	  /* However, defining once as extern inline and a second
	     time in another way is ok.  */
	  && ! (DECL_DECLARED_INLINE_P (olddecl) && DECL_EXTERNAL (olddecl)
	       && ! (DECL_DECLARED_INLINE_P (newdecl)
		     && DECL_EXTERNAL (newdecl))))
	return 1;
      return 0;
    }
  else if (DECL_CONTEXT (newdecl) == NULL_TREE)
    {
      /* Objects declared at top level:  */
      /* If at least one is a reference, it's ok.  */
      if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
	return 0;
      /* Reject two definitions.  */
      if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0)
	return 1;
      /* Now we have two tentative defs, or one tentative and one real def.  */
      /* Insist that the linkage match.  */
      if (TREE_PUBLIC (olddecl) != TREE_PUBLIC (newdecl))
	return 3;
      return 0;
    }
  else if (current_binding_level->parm_flag
	   && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
    return 0;
  else
    {
      /* Newdecl has block scope.  If olddecl has block scope also, then
	 reject two definitions, and reject a definition together with an
	 external reference.  Otherwise, it is OK, because newdecl must
	 be an extern reference to olddecl.  */
      if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl))
	  && DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl))
	return 2;
      return 0;
    }
}

/* Get the LABEL_DECL corresponding to identifier ID as a label.
   Create one if none exists so far for the current function.
   This function is called for both label definitions and label references.  */

tree
lookup_label (id)
     tree id;
{
  tree decl = IDENTIFIER_LABEL_VALUE (id);

  if (current_function_decl == 0)
    {
      error ("label %s referenced outside of any function",
	     IDENTIFIER_POINTER (id));
      return 0;
    }

  /* Use a label already defined or ref'd with this name.  */
  if (decl != 0)
    {
      /* But not if it is inherited and wasn't declared to be inheritable.  */
      if (DECL_CONTEXT (decl) != current_function_decl
	  && ! C_DECLARED_LABEL_FLAG (decl))
	return shadow_label (id);
      return decl;
    }

  decl = build_decl (LABEL_DECL, id, void_type_node);

  /* A label not explicitly declared must be local to where it's ref'd.  */
  DECL_CONTEXT (decl) = current_function_decl;

  DECL_MODE (decl) = VOIDmode;

  /* Say where one reference is to the label,
     for the sake of the error if it is not defined.  */
  DECL_SOURCE_LINE (decl) = lineno;
  DECL_SOURCE_FILE (decl) = input_filename;

  IDENTIFIER_LABEL_VALUE (id) = decl;

  named_labels = tree_cons (NULL_TREE, decl, named_labels);

  return decl;
}

/* Make a label named NAME in the current function,
   shadowing silently any that may be inherited from containing functions
   or containing scopes.

   Note that valid use, if the label being shadowed
   comes from another scope in the same function,
   requires calling declare_nonlocal_label right away.  */

tree
shadow_label (name)
     tree name;
{
  tree decl = IDENTIFIER_LABEL_VALUE (name);

  if (decl != 0)
    {
      tree dup;

      /* Check to make sure that the label hasn't already been declared
	 at this label scope */
      for (dup = named_labels; dup; dup = TREE_CHAIN (dup))
	if (TREE_VALUE (dup) == decl)
	  {
	    error ("duplicate label declaration `%s'",
		   IDENTIFIER_POINTER (name));
	    error_with_decl (TREE_VALUE (dup),
			     "this is a previous declaration");
	    /* Just use the previous declaration.  */
	    return lookup_label (name);
	  }

      shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
      IDENTIFIER_LABEL_VALUE (name) = decl = 0;
    }

  return lookup_label (name);
}

/* Define a label, specifying the location in the source file.
   Return the LABEL_DECL node for the label, if the definition is valid.
   Otherwise return 0.  */

tree
define_label (filename, line, name)
     const char *filename;
     int line;
     tree name;
{
  tree decl = lookup_label (name);

  /* If label with this name is known from an outer context, shadow it.  */
  if (decl != 0 && DECL_CONTEXT (decl) != current_function_decl)
    {
      shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
      IDENTIFIER_LABEL_VALUE (name) = 0;
      decl = lookup_label (name);
    }

  if (warn_traditional && !in_system_header && lookup_name (name))
    warning_with_file_and_line (filename, line,
				"traditional C lacks a separate namespace for labels, identifier `%s' conflicts",
				IDENTIFIER_POINTER (name));

  if (DECL_INITIAL (decl) != 0)
    {
      error_with_file_and_line (filename, line, "duplicate label `%s'",
				IDENTIFIER_POINTER (name));
      return 0;
    }
  else
    {
      /* Mark label as having been defined.  */
      DECL_INITIAL (decl) = error_mark_node;
      /* Say where in the source.  */
      DECL_SOURCE_FILE (decl) = filename;
      DECL_SOURCE_LINE (decl) = line;
      return decl;
    }
}

/* 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 ()
{
  return current_binding_level->names;
}

/* Return the list of type-tags (for structs, etc) of the current level.  */

tree
gettags ()
{
  return current_binding_level->tags;
}

/* Store the list of declarations of the current level.
   This is done for the parameter declarations of a function being defined,
   after they are modified in the light of any missing parameters.  */

static void
storedecls (decls)
     tree decls;
{
  current_binding_level->names = decls;
}

/* Similarly, store the list of tags of the current level.  */

static void
storetags (tags)
     tree tags;
{
  current_binding_level->tags = tags;
}

/* Given NAME, an IDENTIFIER_NODE,
   return the structure (or union or enum) definition for that name.
   Searches binding levels from BINDING_LEVEL up to the global level.
   If THISLEVEL_ONLY is nonzero, searches only the specified context
   (but skips any tag-transparent contexts to find one that is
   meaningful for tags).
   CODE says which kind of type the caller wants;
   it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
   If the wrong kind of type is found, an error is reported.  */

static tree
lookup_tag (code, name, binding_level, thislevel_only)
     enum tree_code code;
     struct binding_level *binding_level;
     tree name;
     int thislevel_only;
{
  struct binding_level *level;
  int thislevel = 1;

  for (level = binding_level; level; level = level->level_chain)
    {
      tree tail;
      for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
	{
	  if (TREE_PURPOSE (tail) == name)
	    {
	      if (TREE_CODE (TREE_VALUE (tail)) != code)
		{
		  /* Definition isn't the kind we were looking for.  */
		  pending_invalid_xref = name;
		  pending_invalid_xref_file = input_filename;
		  pending_invalid_xref_line = lineno;
		  /* If in the same binding level as a declaration as a tag
		     of a different type, this must not be allowed to
		     shadow that tag, so give the error immediately.
		     (For example, "struct foo; union foo;" is invalid.)  */
		  if (thislevel)
		    pending_xref_error ();
		}
	      return TREE_VALUE (tail);
	    }
	}
      if (! level->tag_transparent)
	{
	  if (thislevel_only)
	    return NULL_TREE;
	  thislevel = 0;
	}
    }
  return NULL_TREE;
}

/* Print an error message now
   for a recent invalid struct, union or enum cross reference.
   We don't print them immediately because they are not invalid
   when used in the `struct foo;' construct for shadowing.  */

void
pending_xref_error ()
{
  if (pending_invalid_xref != 0)
    error_with_file_and_line (pending_invalid_xref_file,
			      pending_invalid_xref_line,
			      "`%s' defined as wrong kind of tag",
			      IDENTIFIER_POINTER (pending_invalid_xref));
  pending_invalid_xref = 0;
}

/* Given a type, find the tag that was defined for it and return the tag name.
   Otherwise return 0.  */

static tree
lookup_tag_reverse (type)
     tree type;
{
  struct binding_level *level;

  for (level = current_binding_level; level; level = level->level_chain)
    {
      tree tail;
      for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
	{
	  if (TREE_VALUE (tail) == type)
	    return TREE_PURPOSE (tail);
	}
    }
  return 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,
   or return 0 if it is undefined.  */

tree
lookup_name (name)
     tree name;
{
  tree val;

  if (current_binding_level != global_binding_level
      && IDENTIFIER_LOCAL_VALUE (name))
    val = IDENTIFIER_LOCAL_VALUE (name);
  else
    val = IDENTIFIER_GLOBAL_VALUE (name);
  return val;
}

/* Similar to `lookup_name' but look only at current binding level.  */

tree
lookup_name_current_level (name)
     tree name;
{
  tree t;

  if (current_binding_level == global_binding_level)
    return IDENTIFIER_GLOBAL_VALUE (name);

  if (IDENTIFIER_LOCAL_VALUE (name) == 0)
    return 0;

  for (t = current_binding_level->names; t; t = TREE_CHAIN (t))
    if (DECL_NAME (t) == name)
      break;

  return t;
}

/* Mark ARG for GC.  */

static void
mark_binding_level (arg)
     void *arg;
{
  struct binding_level *level = *(struct binding_level **) arg;

  for (; level != 0; level = level->level_chain)
    {
      ggc_mark_tree (level->names);
      ggc_mark_tree (level->tags);
      ggc_mark_tree (level->shadowed);
      ggc_mark_tree (level->blocks);
      ggc_mark_tree (level->this_block);
      ggc_mark_tree (level->parm_order);
    }
}

/* Create the predefined scalar types of C,
   and some nodes representing standard constants (0, 1, (void *) 0).
   Initialize the global binding level.
   Make definitions for built-in primitive functions.  */

void
c_init_decl_processing ()
{
  tree endlink;
  tree ptr_ftype_void, ptr_ftype_ptr;

  /* Adds some ggc roots, and reserved words for c-parse.in.  */
  c_parse_init ();

  current_function_decl = NULL;
  named_labels = NULL;
  current_binding_level = NULL_BINDING_LEVEL;
  free_binding_level = NULL_BINDING_LEVEL;

  /* Make the binding_level structure for global names.  */
  pushlevel (0);
  global_binding_level = current_binding_level;

  build_common_tree_nodes (flag_signed_char);

  c_common_nodes_and_builtins ();

  boolean_type_node = integer_type_node;
  boolean_true_node = integer_one_node;
  boolean_false_node = integer_zero_node;

  c_bool_type_node = make_unsigned_type (BOOL_TYPE_SIZE);
  TREE_SET_CODE (c_bool_type_node, BOOLEAN_TYPE);
  TYPE_MAX_VALUE (c_bool_type_node) = build_int_2 (1, 0);
  TREE_TYPE (TYPE_MAX_VALUE (c_bool_type_node)) = c_bool_type_node;
  TYPE_PRECISION (c_bool_type_node) = 1;
  pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
			c_bool_type_node));
  c_bool_false_node = build_int_2 (0, 0);
  TREE_TYPE (c_bool_false_node) = c_bool_type_node;
  c_bool_true_node = build_int_2 (1, 0);
  TREE_TYPE (c_bool_true_node) = c_bool_type_node;

  endlink = void_list_node;
  ptr_ftype_void = build_function_type (ptr_type_node, endlink);
  ptr_ftype_ptr
    = build_function_type (ptr_type_node,
			   tree_cons (NULL_TREE, ptr_type_node, endlink));

  pedantic_lvalues = pedantic;

  make_fname_decl = c_make_fname_decl;
  start_fname_decls ();

  /* Record our roots.  */

  ggc_add_tree_root (c_global_trees, CTI_MAX);
  ggc_add_root (&c_stmt_tree, 1, sizeof c_stmt_tree, mark_stmt_tree);
  ggc_add_tree_root (&c_scope_stmt_stack, 1);
  ggc_add_tree_root (&named_labels, 1);
  ggc_add_tree_root (&shadowed_labels, 1);
  ggc_add_root (&current_binding_level, 1, sizeof current_binding_level,
		mark_binding_level);
  ggc_add_root (&label_level_chain, 1, sizeof label_level_chain,
		mark_binding_level);
  ggc_add_tree_root (&static_ctors, 1);
  ggc_add_tree_root (&static_dtors, 1);
}

/* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
   decl, NAME is the initialization string and TYPE_DEP indicates whether
   NAME depended on the type of the function.  As we don't yet implement
   delayed emission of static data, we mark the decl as emitted
   so it is not placed in the output.  Anything using it must therefore pull
   out the STRING_CST initializer directly.  This does mean that these names
   are string merging candidates, which is wrong for C99's __func__.  FIXME.  */

static tree
c_make_fname_decl (id, type_dep)
     tree id;
     int type_dep;
{
  const char *name = fname_as_string (type_dep);
  tree decl, type, init;
  size_t length = strlen (name);

  type =  build_array_type
          (build_qualified_type (char_type_node, TYPE_QUAL_CONST),
	   build_index_type (size_int (length)));

  decl = build_decl (VAR_DECL, id, type);
  /* We don't push the decl, so have to set its context here.  */
  DECL_CONTEXT (decl) = current_function_decl;
  
  TREE_STATIC (decl) = 1;
  TREE_READONLY (decl) = 1;
  DECL_ARTIFICIAL (decl) = 1;
  
  init = build_string (length + 1, name);
  TREE_TYPE (init) = type;
  DECL_INITIAL (decl) = init;

  TREE_USED (decl) = 1;
  
  finish_decl (decl, init, NULL_TREE);

  return decl;
}

/* Return a definition for a builtin function named NAME and whose data type
   is TYPE.  TYPE should be a function type with argument types.
   FUNCTION_CODE tells later passes how to compile calls to this function.
   See tree.h for its possible values.

   If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
   the name to be called if we can't opencode the function.  */

tree
builtin_function (name, type, function_code, class, library_name)
     const char *name;
     tree type;
     int function_code;
     enum built_in_class class;
     const char *library_name;
{
  tree decl = build_decl (FUNCTION_DECL, get_identifier (name), type);
  DECL_EXTERNAL (decl) = 1;
  TREE_PUBLIC (decl) = 1;
  if (library_name)
    SET_DECL_ASSEMBLER_NAME (decl, get_identifier (library_name));
  make_decl_rtl (decl, NULL);
  pushdecl (decl);
  DECL_BUILT_IN_CLASS (decl) = class;
  DECL_FUNCTION_CODE (decl) = function_code;

  /* The return builtins leave the current function.  */
  if (function_code == BUILT_IN_RETURN || function_code == BUILT_IN_EH_RETURN)
    TREE_THIS_VOLATILE (decl) = 1;

  /* Warn if a function in the namespace for users
     is used without an occasion to consider it declared.  */
  if (name[0] != '_' || name[1] != '_')
    C_DECL_ANTICIPATED (decl) = 1;

  /* Possibly apply some default attributes to this built-in function.  */
  decl_attributes (&decl, NULL_TREE, 0);

  return decl;
}

/* Apply default attributes to a function, if a system function with default
   attributes.  */

void
c_insert_default_attributes (decl)
     tree decl;
{
  if (!TREE_PUBLIC (decl))
    return;
  c_common_insert_default_attributes (decl);
}

/* Called when a declaration is seen that contains no names to declare.
   If its type is a reference to a structure, union or enum inherited
   from a containing scope, shadow that tag name for the current scope
   with a forward reference.
   If its type defines a new named structure or union
   or defines an enum, it is valid but we need not do anything here.
   Otherwise, it is an error.  */

void
shadow_tag (declspecs)
     tree declspecs;
{
  shadow_tag_warned (declspecs, 0);
}

void
shadow_tag_warned (declspecs, warned)
     tree declspecs;
     int warned;
     /* 1 => we have done a pedwarn.  2 => we have done a warning, but
	no pedwarn.  */
{
  int found_tag = 0;
  tree link;
  tree specs, attrs;

  pending_invalid_xref = 0;

  /* Remove the attributes from declspecs, since they will confuse the
     following code.  */
  split_specs_attrs (declspecs, &specs, &attrs);

  for (link = specs; link; link = TREE_CHAIN (link))
    {
      tree value = TREE_VALUE (link);
      enum tree_code code = TREE_CODE (value);

      if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
	/* Used to test also that TYPE_SIZE (value) != 0.
	   That caused warning for `struct foo;' at top level in the file.  */
	{
	  tree name = lookup_tag_reverse (value);
	  tree t;

	  found_tag++;

	  if (name == 0)
	    {
	      if (warned != 1 && code != ENUMERAL_TYPE)
		/* Empty unnamed enum OK */
		{
		  pedwarn ("unnamed struct/union that defines no instances");
		  warned = 1;
		}
	    }
	  else
	    {
	      t = lookup_tag (code, name, current_binding_level, 1);

	      if (t == 0)
		{
		  t = make_node (code);
		  pushtag (name, t);
		}
	    }
	}
      else
	{
	  if (!warned && ! in_system_header)
	    {
	      warning ("useless keyword or type name in empty declaration");
	      warned = 2;
	    }
	}
    }

  if (found_tag > 1)
    error ("two types specified in one empty declaration");

  if (warned != 1)
    {
      if (found_tag == 0)
	pedwarn ("empty declaration");
    }
}

/* Construct an array declarator.  EXPR is the expression inside [], or
   NULL_TREE.  QUALS are the type qualifiers inside the [] (to be applied
   to the pointer to which a parameter array is converted).  STATIC_P is
   non-zero if "static" is inside the [], zero otherwise.  VLA_UNSPEC_P
   is non-zero is the array is [*], a VLA of unspecified length which is
   nevertheless a complete type (not currently implemented by GCC),
   zero otherwise.  The declarator is constructed as an ARRAY_REF
   (to be decoded by grokdeclarator), whose operand 0 is what's on the
   left of the [] (filled by in set_array_declarator_type) and operand 1
   is the expression inside; whose TREE_TYPE is the type qualifiers and
   which has TREE_STATIC set if "static" is used.  */

tree
build_array_declarator (expr, quals, static_p, vla_unspec_p)
     tree expr;
     tree quals;
     int static_p;
     int vla_unspec_p;
{
  tree decl;
  decl = build_nt (ARRAY_REF, NULL_TREE, expr);
  TREE_TYPE (decl) = quals;
  TREE_STATIC (decl) = (static_p ? 1 : 0);
  if (pedantic && !flag_isoc99)
    {
      if (static_p || quals != NULL_TREE)
	pedwarn ("ISO C89 does not support `static' or type qualifiers in parameter array declarators");
      if (vla_unspec_p)
	pedwarn ("ISO C89 does not support `[*]' array declarators");
    }
  if (vla_unspec_p)
    warning ("GCC does not yet properly implement `[*]' array declarators");
  return decl;
}

/* Set the type of an array declarator.  DECL is the declarator, as
   constructed by build_array_declarator; TYPE is what appears on the left
   of the [] and goes in operand 0.  ABSTRACT_P is non-zero if it is an
   abstract declarator, zero otherwise; this is used to reject static and
   type qualifiers in abstract declarators, where they are not in the
   C99 grammar.  */

tree
set_array_declarator_type (decl, type, abstract_p)
     tree decl;
     tree type;
     int abstract_p;
{
  TREE_OPERAND (decl, 0) = type;
  if (abstract_p && (TREE_TYPE (decl) != NULL_TREE || TREE_STATIC (decl)))
    error ("static or type qualifiers in abstract declarator");
  return decl;
}

/* Decode a "typename", such as "int **", returning a ..._TYPE node.  */

tree
groktypename (typename)
     tree typename;
{
  tree specs, attrs;

  if (TREE_CODE (typename) != TREE_LIST)
    return typename;

  split_specs_attrs (TREE_PURPOSE (typename), &specs, &attrs);

  typename = grokdeclarator (TREE_VALUE (typename), specs, TYPENAME, 0);

  /* Apply attributes.  */
  decl_attributes (&typename, attrs, 0);

  return typename;
}

/* Return a PARM_DECL node for a given pair of specs and declarator.  */

tree
groktypename_in_parm_context (typename)
     tree typename;
{
  if (TREE_CODE (typename) != TREE_LIST)
    return typename;
  return grokdeclarator (TREE_VALUE (typename),
			 TREE_PURPOSE (typename),
			 PARM, 0);
}

/* Decode a declarator in an ordinary declaration or data definition.
   This is called as soon as the type information and variable name
   have been parsed, before parsing the initializer if any.
   Here we create the ..._DECL node, fill in its type,
   and put it on the list of decls for the current context.
   The ..._DECL node is returned as the value.

   Exception: for arrays where the length is not specified,
   the type is left null, to be filled in by `finish_decl'.

   Function definitions do not come here; they go to start_function
   instead.  However, external and forward declarations of functions
   do go through here.  Structure field declarations are done by
   grokfield and not through here.  */

tree
start_decl (declarator, declspecs, initialized, attributes)
     tree declarator, declspecs;
     int initialized;
     tree attributes;
{
  tree decl;
  tree tem;
  
  /* An object declared as __attribute__((deprecated)) suppresses
     warnings of uses of other deprecated items.  */
  if (lookup_attribute ("deprecated", attributes))
    deprecated_state = DEPRECATED_SUPPRESS;

  decl = grokdeclarator (declarator, declspecs,
			 NORMAL, initialized);
  
  deprecated_state = DEPRECATED_NORMAL;

  if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
      && MAIN_NAME_P (DECL_NAME (decl)))
    warning_with_decl (decl, "`%s' is usually a function");

  if (initialized)
    /* Is it valid for this decl to have an initializer at all?
       If not, set INITIALIZED to zero, which will indirectly
       tell `finish_decl' to ignore the initializer once it is parsed.  */
    switch (TREE_CODE (decl))
      {
      case TYPE_DECL:
	/* typedef foo = bar  means give foo the same type as bar.
	   We haven't parsed bar yet, so `finish_decl' will fix that up.
	   Any other case of an initialization in a TYPE_DECL is an error.  */
	if (pedantic || list_length (declspecs) > 1)
	  {
	    error ("typedef `%s' is initialized",
		   IDENTIFIER_POINTER (DECL_NAME (decl)));
	    initialized = 0;
	  }
	break;

      case FUNCTION_DECL:
	error ("function `%s' is initialized like a variable",
	       IDENTIFIER_POINTER (DECL_NAME (decl)));
	initialized = 0;
	break;

      case PARM_DECL:
	/* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE.  */
	error ("parameter `%s' is initialized",
	       IDENTIFIER_POINTER (DECL_NAME (decl)));
	initialized = 0;
	break;

      default:
	/* Don't allow initializations for incomplete types
	   except for arrays which might be completed by the initialization.  */

	/* This can happen if the array size is an undefined macro.  We already
	   gave a warning, so we don't need another one.  */
	if (TREE_TYPE (decl) == error_mark_node)
	  initialized = 0;
	else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
	  {
	    /* A complete type is ok if size is fixed.  */

	    if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
		|| C_DECL_VARIABLE_SIZE (decl))
	      {
		error ("variable-sized object may not be initialized");
		initialized = 0;
	      }
	  }
	else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
	  {
	    error ("variable `%s' has initializer but incomplete type",
		   IDENTIFIER_POINTER (DECL_NAME (decl)));
	    initialized = 0;
	  }
	else if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
	  {
	    error ("elements of array `%s' have incomplete type",
		   IDENTIFIER_POINTER (DECL_NAME (decl)));
	    initialized = 0;
	  }
      }

  if (initialized)
    {
#if 0
      /* Seems redundant with grokdeclarator.  */
      if (current_binding_level != global_binding_level
	  && DECL_EXTERNAL (decl)
	  && TREE_CODE (decl) != FUNCTION_DECL)
	warning ("declaration of `%s' has `extern' and is initialized",
		 IDENTIFIER_POINTER (DECL_NAME (decl)));
#endif
      DECL_EXTERNAL (decl) = 0;
      if (current_binding_level == global_binding_level)
	TREE_STATIC (decl) = 1;

      /* Tell `pushdecl' this is an initialized decl
	 even though we don't yet have the initializer expression.
	 Also tell `finish_decl' it may store the real initializer.  */
      DECL_INITIAL (decl) = error_mark_node;
    }

  /* If this is a function declaration, write a record describing it to the
     prototypes file (if requested).  */

  if (TREE_CODE (decl) == FUNCTION_DECL)
    gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);

  /* ANSI specifies that a tentative definition which is not merged with
     a non-tentative definition behaves exactly like a definition with an
     initializer equal to zero.  (Section 3.7.2)

     -fno-common gives strict ANSI behavior, though this tends to break
     a large body of code that grew up without this rule.

     Thread-local variables are never common, since there's no entrenched
     body of code to break, and it allows more efficient variable references
     in the presense of dynamic linking.  */

  if (TREE_CODE (decl) == VAR_DECL
      && !initialized
      && TREE_PUBLIC (decl)
      && !DECL_THREAD_LOCAL (decl)
      && !flag_no_common)
    DECL_COMMON (decl) = 1;

  /* Set attributes here so if duplicate decl, will have proper attributes.  */
  decl_attributes (&decl, attributes, 0);

  /* If #pragma weak was used, mark the decl weak now.  */
  if (current_binding_level == global_binding_level)
    maybe_apply_pragma_weak (decl);

  if (TREE_CODE (decl) == FUNCTION_DECL
      && DECL_DECLARED_INLINE_P (decl)
      && DECL_UNINLINABLE (decl)
      && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
    warning_with_decl (decl,
		       "inline function `%s' given attribute noinline");

  /* Add this decl to the current binding level.
     TEM may equal DECL or it may be a previous decl of the same name.  */
  tem = pushdecl (decl);

  /* For a local variable, define the RTL now.  */
  if (current_binding_level != global_binding_level
      /* But not if this is a duplicate decl
	 and we preserved the rtl from the previous one
	 (which may or may not happen).  */
      && !DECL_RTL_SET_P (tem)
      && !DECL_CONTEXT (tem))
    {
      if (TREE_TYPE (tem) != error_mark_node
	  && COMPLETE_TYPE_P (TREE_TYPE (tem)))
	expand_decl (tem);
      else if (TREE_CODE (TREE_TYPE (tem)) == ARRAY_TYPE
	       && DECL_INITIAL (tem) != 0)
	expand_decl (tem);
    }

  return tem;
}

/* Finish processing of a declaration;
   install its initial value.
   If the length of an array type is not known before,
   it must be determined now, from the initial value, or it is an error.  */

void
finish_decl (decl, init, asmspec_tree)
     tree decl, init;
     tree asmspec_tree;
{
  tree type = TREE_TYPE (decl);
  int was_incomplete = (DECL_SIZE (decl) == 0);
  const char *asmspec = 0;

  /* If a name was specified, get the string.  */
  if (current_binding_level == global_binding_level)
    asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
  if (asmspec_tree)
    asmspec = TREE_STRING_POINTER (asmspec_tree);

  /* If `start_decl' didn't like having an initialization, ignore it now.  */
  if (init != 0 && DECL_INITIAL (decl) == 0)
    init = 0;
  
  /* Don't crash if parm is initialized.  */
  if (TREE_CODE (decl) == PARM_DECL)
    init = 0;

  if (init)
    {
      if (TREE_CODE (decl) != TYPE_DECL)
	store_init_value (decl, init);
      else
	{
	  /* typedef foo = bar; store the type of bar as the type of foo.  */
	  TREE_TYPE (decl) = TREE_TYPE (init);
	  DECL_INITIAL (decl) = init = 0;
	}
    }

  /* Deduce size of array from initialization, if not already known */
  if (TREE_CODE (type) == ARRAY_TYPE
      && TYPE_DOMAIN (type) == 0
      && TREE_CODE (decl) != TYPE_DECL)
    {
      int do_default
	= (TREE_STATIC (decl)
	   /* Even if pedantic, an external linkage array
	      may have incomplete type at first.  */
	   ? pedantic && !TREE_PUBLIC (decl)
	   : !DECL_EXTERNAL (decl));
      int failure
	= complete_array_type (type, DECL_INITIAL (decl), do_default);

      /* Get the completed type made by complete_array_type.  */
      type = TREE_TYPE (decl);

      if (failure == 1)
	error_with_decl (decl, "initializer fails to determine size of `%s'");

      else if (failure == 2)
	{
	  if (do_default)
	    error_with_decl (decl, "array size missing in `%s'");
	  /* If a `static' var's size isn't known,
	     make it extern as well as static, so it does not get
	     allocated.
	     If it is not `static', then do not mark extern;
	     finish_incomplete_decl will give it a default size
	     and it will get allocated.  */
	  else if (!pedantic && TREE_STATIC (decl) && ! TREE_PUBLIC (decl))
	    DECL_EXTERNAL (decl) = 1;
	}

      /* TYPE_MAX_VALUE is always one less than the number of elements
	 in the array, because we start counting at zero.  Therefore,
	 warn only if the value is less than zero.  */
      else if (pedantic && TYPE_DOMAIN (type) != 0
	      && tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) < 0)
	error_with_decl (decl, "zero or negative size array `%s'");

      layout_decl (decl, 0);
    }

  if (TREE_CODE (decl) == VAR_DECL)
    {
      if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
	  && COMPLETE_TYPE_P (TREE_TYPE (decl)))
	layout_decl (decl, 0);

      if (DECL_SIZE (decl) == 0
	  /* Don't give an error if we already gave one earlier.  */
	  && TREE_TYPE (decl) != error_mark_node
	  && (TREE_STATIC (decl)
	      ?
		/* A static variable with an incomplete type
		   is an error if it is initialized.
		   Also if it is not file scope.
		   Otherwise, let it through, but if it is not `extern'
		   then it may cause an error message later.  */
		(DECL_INITIAL (decl) != 0
		 || DECL_CONTEXT (decl) != 0)
	      :
		/* An automatic variable with an incomplete type
		   is an error.  */
		!DECL_EXTERNAL (decl)))
	{
	  error_with_decl (decl, "storage size of `%s' isn't known");
	  TREE_TYPE (decl) = error_mark_node;
	}

      if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
	  && DECL_SIZE (decl) != 0)
	{
	  if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
	    constant_expression_warning (DECL_SIZE (decl));
	  else
	    error_with_decl (decl, "storage size of `%s' isn't constant");
	}

      if (TREE_USED (type))
	TREE_USED (decl) = 1;
    }

  /* If this is a function and an assembler name is specified, it isn't
     builtin any more.  Also reset DECL_RTL so we can give it its new
     name.  */
  if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
    {
      DECL_BUILT_IN_CLASS (decl) = NOT_BUILT_IN;
      SET_DECL_RTL (decl, NULL_RTX);
      SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
    }

  /* Output the assembler code and/or RTL code for variables and functions,
     unless the type is an undefined structure or union.
     If not, it will get done when the type is completed.  */

  if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
    {
      /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
      maybe_objc_check_decl (decl);

      if (!DECL_CONTEXT (decl))
	{
	  if (DECL_INITIAL (decl) == NULL_TREE
	      || DECL_INITIAL (decl) == error_mark_node)
	    /* Don't output anything
	       when a tentative file-scope definition is seen.
	       But at end of compilation, do output code for them.  */
	    DECL_DEFER_OUTPUT (decl) = 1;
	  rest_of_decl_compilation (decl, asmspec,
				    (DECL_CONTEXT (decl) == 0
				     || TREE_ASM_WRITTEN (decl)), 0);
	}
      else
	{
	  /* This is a local variable.  If there is an ASMSPEC, the
	     user has requested that we handle it specially.  */
	  if (asmspec)
	    {
	      /* In conjunction with an ASMSPEC, the `register'
		 keyword indicates that we should place the variable
		 in a particular register.  */
	      if (DECL_REGISTER (decl))
		DECL_C_HARD_REGISTER (decl) = 1;

	      /* If this is not a static variable, issue a warning.
		 It doesn't make any sense to give an ASMSPEC for an
		 ordinary, non-register local variable.  Historically,
		 GCC has accepted -- but ignored -- the ASMSPEC in
		 this case.  */
	      if (TREE_CODE (decl) == VAR_DECL 
		  && !DECL_REGISTER (decl)
		  && !TREE_STATIC (decl))
		warning_with_decl (decl,
				   "ignoring asm-specifier for non-static local variable `%s'");
	      else
		SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
	    }

	  if (TREE_CODE (decl) != FUNCTION_DECL)
	    add_decl_stmt (decl);
	}

      if (DECL_CONTEXT (decl) != 0)
	{
	  /* Recompute the RTL of a local array now
	     if it used to be an incomplete type.  */
	  if (was_incomplete
	      && ! TREE_STATIC (decl) && ! DECL_EXTERNAL (decl))
	    {
	      /* If we used it already as memory, it must stay in memory.  */
	      TREE_ADDRESSABLE (decl) = TREE_USED (decl);
	      /* If it's still incomplete now, no init will save it.  */
	      if (DECL_SIZE (decl) == 0)
		DECL_INITIAL (decl) = 0;
	    }
	}
    }

  if (TREE_CODE (decl) == TYPE_DECL)
    {
      /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
      maybe_objc_check_decl (decl);
      rest_of_decl_compilation (decl, NULL, DECL_CONTEXT (decl) == 0, 0);
    }

  /* At the end of a declaration, throw away any variable type sizes
     of types defined inside that declaration.  There is no use
     computing them in the following function definition.  */
  if (current_binding_level == global_binding_level)
    get_pending_sizes ();
}

/* Given a parsed parameter declaration,
   decode it into a PARM_DECL and push that on the current binding level.
   Also, for the sake of forward parm decls,
   record the given order of parms in `parm_order'.  */

void
push_parm_decl (parm)
     tree parm;
{
  tree decl;
  int old_immediate_size_expand = immediate_size_expand;
  /* Don't try computing parm sizes now -- wait till fn is called.  */
  immediate_size_expand = 0;

  decl = grokdeclarator (TREE_VALUE (TREE_PURPOSE (parm)),
			 TREE_PURPOSE (TREE_PURPOSE (parm)), PARM, 0);
  decl_attributes (&decl, TREE_VALUE (parm), 0);

#if 0
  if (DECL_NAME (decl))
    {
      tree olddecl;
      olddecl = lookup_name (DECL_NAME (decl));
      if (pedantic && olddecl != 0 && TREE_CODE (olddecl) == TYPE_DECL)
	pedwarn_with_decl (decl,
			   "ISO C forbids parameter `%s' shadowing typedef");
    }
#endif

  decl = pushdecl (decl);

  immediate_size_expand = old_immediate_size_expand;

  current_binding_level->parm_order
    = tree_cons (NULL_TREE, decl, current_binding_level->parm_order);

  /* Add this decl to the current binding level.  */
  finish_decl (decl, NULL_TREE, NULL_TREE);
}

/* Clear the given order of parms in `parm_order'.
   Used at start of parm list,
   and also at semicolon terminating forward decls.  */

void
clear_parm_order ()
{
  current_binding_level->parm_order = NULL_TREE;
}

/* Build a COMPOUND_LITERAL_EXPR.  TYPE is the type given in the compound
   literal, which may be an incomplete array type completed by the
   initializer; INIT is a CONSTRUCTOR that initializes the compound
   literal.  */

tree
build_compound_literal (type, init)
     tree type;
     tree init;
{
  /* We do not use start_decl here because we have a type, not a declarator;
     and do not use finish_decl because the decl should be stored inside
     the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_STMT.  */
  tree decl = build_decl (VAR_DECL, NULL_TREE, type);
  tree complit;
  tree stmt;
  DECL_EXTERNAL (decl) = 0;
  TREE_PUBLIC (decl) = 0;
  TREE_STATIC (decl) = (current_binding_level == global_binding_level);
  DECL_CONTEXT (decl) = current_function_decl;
  TREE_USED (decl) = 1;
  TREE_TYPE (decl) = type;
  store_init_value (decl, init);

  if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
    {
      int failure = complete_array_type (type, DECL_INITIAL (decl), 1);
      if (failure)
	abort ();
    }

  type = TREE_TYPE (decl);
  if (type == error_mark_node || !COMPLETE_TYPE_P (type))
    return error_mark_node;

  stmt = build_stmt (DECL_STMT, decl);
  complit = build1 (COMPOUND_LITERAL_EXPR, TREE_TYPE (decl), stmt);
  TREE_SIDE_EFFECTS (complit) = 1;

  layout_decl (decl, 0);

  if (TREE_STATIC (decl))
    {
      /* This decl needs a name for the assembler output.  We also need
	 a unique suffix to be added to the name, for which DECL_CONTEXT
	 must be set.  */
      DECL_NAME (decl) = get_identifier ("__compound_literal");
      DECL_CONTEXT (decl) = complit;
      rest_of_decl_compilation (decl, NULL, 1, 0);
      DECL_CONTEXT (decl) = NULL_TREE;
    }

  return complit;
}

/* Make TYPE a complete type based on INITIAL_VALUE.
   Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
   2 if there was no information (in which case assume 1 if DO_DEFAULT).  */

int
complete_array_type (type, initial_value, do_default)
     tree type;
     tree initial_value;
     int do_default;
{
  tree maxindex = NULL_TREE;
  int value = 0;

  if (initial_value)
    {
      /* Note MAXINDEX  is really the maximum index,
	 one less than the size.  */
      if (TREE_CODE (initial_value) == STRING_CST)
	{
	  int eltsize
	    = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
	  maxindex = build_int_2 ((TREE_STRING_LENGTH (initial_value)
				   / eltsize) - 1, 0);
	}
      else if (TREE_CODE (initial_value) == CONSTRUCTOR)
	{
	  tree elts = CONSTRUCTOR_ELTS (initial_value);
	  maxindex = build_int_2 (-1, -1);
	  for (; elts; elts = TREE_CHAIN (elts))
	    {
	      if (TREE_PURPOSE (elts))
		maxindex = TREE_PURPOSE (elts);
	      else
		maxindex = fold (build (PLUS_EXPR, integer_type_node,
					maxindex, integer_one_node));
	    }
	  maxindex = copy_node (maxindex);
	}
      else
	{
	  /* Make an error message unless that happened already.  */
	  if (initial_value != error_mark_node)
	    value = 1;

	  /* Prevent further error messages.  */
	  maxindex = build_int_2 (0, 0);
	}
    }

  if (!maxindex)
    {
      if (do_default)
	maxindex = build_int_2 (0, 0);
      value = 2;
    }

  if (maxindex)
    {
      TYPE_DOMAIN (type) = build_index_type (maxindex);
      if (!TREE_TYPE (maxindex))
	TREE_TYPE (maxindex) = TYPE_DOMAIN (type);
    }

  /* Lay out the type now that we can get the real answer.  */

  layout_type (type);

  return value;
}

/* Given declspecs and a declarator,
   determine the name and type of the object declared
   and construct a ..._DECL node for it.
   (In one case we can return a ..._TYPE node instead.
    For invalid input we sometimes return 0.)

   DECLSPECS is a chain of tree_list nodes whose value fields
    are the storage classes and type specifiers.

   DECL_CONTEXT says which syntactic context this declaration is in:
     NORMAL for most contexts.  Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
     FUNCDEF for a function definition.  Like NORMAL but a few different
      error messages in each case.  Return value may be zero meaning
      this definition is too screwy to try to parse.
     PARM for a parameter declaration (either within a function prototype
      or before a function body).  Make a PARM_DECL, or return void_type_node.
     TYPENAME if for a typename (in a cast or sizeof).
      Don't make a DECL node; just return the ..._TYPE node.
     FIELD for a struct or union field; make a FIELD_DECL.
     BITFIELD for a field with specified width.
   INITIALIZED is 1 if the decl has an initializer.

   In the TYPENAME case, DECLARATOR is really an absolute declarator.
   It may also be so in the PARM case, for a prototype where the
   argument type is specified but not the name.

   This function is where the complicated C meanings of `static'
   and `extern' are interpreted.  */

static tree
grokdeclarator (declarator, declspecs, decl_context, initialized)
     tree declspecs;
     tree declarator;
     enum decl_context decl_context;
     int initialized;
{
  int specbits = 0;
  tree spec;
  tree type = NULL_TREE;
  int longlong = 0;
  int constp;
  int restrictp;
  int volatilep;
  int type_quals = TYPE_UNQUALIFIED;
  int inlinep;
  int explicit_int = 0;
  int explicit_char = 0;
  int defaulted_int = 0;
  tree typedef_decl = 0;
  const char *name;
  tree typedef_type = 0;
  int funcdef_flag = 0;
  enum tree_code innermost_code = ERROR_MARK;
  int bitfield = 0;
  int size_varies = 0;
  tree decl_attr = NULL_TREE;
  tree array_ptr_quals = NULL_TREE;
  int array_parm_static = 0;
  tree returned_attrs = NULL_TREE;

  if (decl_context == BITFIELD)
    bitfield = 1, decl_context = FIELD;

  if (decl_context == FUNCDEF)
    funcdef_flag = 1, decl_context = NORMAL;

  /* Look inside a declarator for the name being declared
     and get it as a string, for an error message.  */
  {
    tree decl = declarator;
    name = 0;

    while (decl)
      switch (TREE_CODE (decl))
	{
	case ARRAY_REF:
	case INDIRECT_REF:
	case CALL_EXPR:
	  innermost_code = TREE_CODE (decl);
	  decl = TREE_OPERAND (decl, 0);
	  break;

	case TREE_LIST:
	  decl = TREE_VALUE (decl);
	  break;

	case IDENTIFIER_NODE:
	  name = IDENTIFIER_POINTER (decl);
	  decl = 0;
	  break;

	default:
	  abort ();
	}
    if (name == 0)
      name = "type name";
  }

  /* A function definition's declarator must have the form of
     a function declarator.  */

  if (funcdef_flag && innermost_code != CALL_EXPR)
    return 0;

  /* Anything declared one level down from the top level
     must be one of the parameters of a function
     (because the body is at least two levels down).  */

  /* If this looks like a function definition, make it one,
     even if it occurs where parms are expected.
     Then store_parm_decls will reject it and not use it as a parm.  */
  if (decl_context == NORMAL && !funcdef_flag
      && current_binding_level->parm_flag)
    decl_context = PARM;

  /* Look through the decl specs and record which ones appear.
     Some typespecs are defined as built-in typenames.
     Others, the ones that are modifiers of other types,
     are represented by bits in SPECBITS: set the bits for
     the modifiers that appear.  Storage class keywords are also in SPECBITS.

     If there is a typedef name or a type, store the type in TYPE.
     This includes builtin typedefs such as `int'.

     Set EXPLICIT_INT or EXPLICIT_CHAR if the type is `int' or `char'
     and did not come from a user typedef.

     Set LONGLONG if `long' is mentioned twice.  */

  for (spec = declspecs; spec; spec = TREE_CHAIN (spec))
    {
      tree id = TREE_VALUE (spec);

      /* If the entire declaration is itself tagged as deprecated then
         suppress reports of deprecated items.  */
      if (id && TREE_DEPRECATED (id))
        {
	  if (deprecated_state != DEPRECATED_SUPPRESS)
	    warn_deprecated_use (id);
        }

      if (id == ridpointers[(int) RID_INT])
	explicit_int = 1;
      if (id == ridpointers[(int) RID_CHAR])
	explicit_char = 1;

      if (TREE_CODE (id) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (id))
	{
	  enum rid i = C_RID_CODE (id);
	  if ((int) i <= (int) RID_LAST_MODIFIER)
	    {
	      if (i == RID_LONG && (specbits & (1 << (int) RID_LONG)))
		{
		  if (longlong)
		    error ("`long long long' is too long for GCC");
		  else
		    {
		      if (pedantic && !flag_isoc99 && ! in_system_header
			  && warn_long_long)
			pedwarn ("ISO C89 does not support `long long'");
		      longlong = 1;
		    }
		}
	      else if (specbits & (1 << (int) i))
		pedwarn ("duplicate `%s'", IDENTIFIER_POINTER (id));

	      /* Diagnose "__thread extern".  Recall that this list
		 is in the reverse order seen in the text.  */
	      if (i == RID_THREAD
		  && (specbits & (1 << (int) RID_EXTERN
				  | 1 << (int) RID_STATIC)))
		{
		  if (specbits & 1 << (int) RID_EXTERN)
		    error ("`__thread' before `extern'");
		  else
		    error ("`__thread' before `static'");
		}

	      specbits |= 1 << (int) i;
	      goto found;
	    }
	}
      if (type)
	error ("two or more data types in declaration of `%s'", name);
      /* Actual typedefs come to us as TYPE_DECL nodes.  */
      else if (TREE_CODE (id) == TYPE_DECL)
	{
	  if (TREE_TYPE (id) == error_mark_node)
	    ; /* Allow the type to default to int to avoid cascading errors.  */
	  else
	    {
	      type = TREE_TYPE (id);
	      decl_attr = DECL_ATTRIBUTES (id);
	      typedef_decl = id;
	    }
	}
      /* Built-in types come as identifiers.  */
      else if (TREE_CODE (id) == IDENTIFIER_NODE)
	{
	  tree t = lookup_name (id);
	  if (TREE_TYPE (t) == error_mark_node)
	    ;
	  else if (!t || TREE_CODE (t) != TYPE_DECL)
	    error ("`%s' fails to be a typedef or built in type",
		   IDENTIFIER_POINTER (id));
	  else
	    {
	      type = TREE_TYPE (t);
	      typedef_decl = t;
	    }
	}
      else if (TREE_CODE (id) != ERROR_MARK)
	type = id;

    found:
      ;
    }

  typedef_type = type;
  if (type)
    size_varies = C_TYPE_VARIABLE_SIZE (type);

  /* No type at all: default to `int', and set DEFAULTED_INT
     because it was not a user-defined typedef.  */

  if (type == 0)
    {
      if ((! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
			  | (1 << (int) RID_SIGNED)
			  | (1 << (int) RID_UNSIGNED)
			  | (1 << (int) RID_COMPLEX))))
	  /* Don't warn about typedef foo = bar.  */
	  && ! (specbits & (1 << (int) RID_TYPEDEF) && initialized)
	  && ! in_system_header)
	{
	  /* Issue a warning if this is an ISO C 99 program or if -Wreturn-type
	     and this is a function, or if -Wimplicit; prefer the former
	     warning since it is more explicit.  */
	  if ((warn_implicit_int || warn_return_type || flag_isoc99)
	      && funcdef_flag)
	    warn_about_return_type = 1;
	  else if (warn_implicit_int || flag_isoc99)
	    pedwarn_c99 ("type defaults to `int' in declaration of `%s'",
			 name);
	}

      defaulted_int = 1;
      type = integer_type_node;
    }

  /* Now process the modifiers that were specified
     and check for invalid combinations.  */

  /* Long double is a special combination.  */

  if ((specbits & 1 << (int) RID_LONG) && ! longlong
      && TYPE_MAIN_VARIANT (type) == double_type_node)
    {
      specbits &= ~(1 << (int) RID_LONG);
      type = long_double_type_node;
    }

  /* Check all other uses of type modifiers.  */

  if (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
		  | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED)))
    {
      int ok = 0;

      if ((specbits & 1 << (int) RID_LONG)
	  && (specbits & 1 << (int) RID_SHORT))
	error ("both long and short specified for `%s'", name);
      else if (((specbits & 1 << (int) RID_LONG)
		|| (specbits & 1 << (int) RID_SHORT))
	       && explicit_char)
	error ("long or short specified with char for `%s'", name);
      else if (((specbits & 1 << (int) RID_LONG)
		|| (specbits & 1 << (int) RID_SHORT))
	       && TREE_CODE (type) == REAL_TYPE)
	{
	  static int already = 0;

	  error ("long or short specified with floating type for `%s'", name);
	  if (! already && ! pedantic)
	    {
	      error ("the only valid combination is `long double'");
	      already = 1;
	    }
	}
      else if ((specbits & 1 << (int) RID_SIGNED)
	       && (specbits & 1 << (int) RID_UNSIGNED))
	error ("both signed and unsigned specified for `%s'", name);
      else if (TREE_CODE (type) != INTEGER_TYPE)
	error ("long, short, signed or unsigned invalid for `%s'", name);
      else
	{
	  ok = 1;
	  if (!explicit_int && !defaulted_int && !explicit_char && pedantic)
	    {
	      pedwarn ("long, short, signed or unsigned used invalidly for `%s'",
		       name);
	      if (flag_pedantic_errors)
		ok = 0;
	    }
	}

      /* Discard the type modifiers if they are invalid.  */
      if (! ok)
	{
	  specbits &= ~((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
			| (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED));
	  longlong = 0;
	}
    }

  if ((specbits & (1 << (int) RID_COMPLEX))
      && TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
    {
      error ("complex invalid for `%s'", name);
      specbits &= ~(1 << (int) RID_COMPLEX);
    }

  /* Decide whether an integer type is signed or not.
     Optionally treat bitfields as signed by default.  */
  if (specbits & 1 << (int) RID_UNSIGNED
      || (bitfield && ! flag_signed_bitfields
	  && (explicit_int || defaulted_int || explicit_char
	      /* A typedef for plain `int' without `signed'
		 can be controlled just like plain `int'.  */
	      || ! (typedef_decl != 0
		    && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
	  && TREE_CODE (type) != ENUMERAL_TYPE
	  && !(specbits & 1 << (int) RID_SIGNED)))
    {
      if (longlong)
	type = long_long_unsigned_type_node;
      else if (specbits & 1 << (int) RID_LONG)
	type = long_unsigned_type_node;
      else if (specbits & 1 << (int) RID_SHORT)
	type = short_unsigned_type_node;
      else if (type == char_type_node)
	type = unsigned_char_type_node;
      else if (typedef_decl)
	type = c_common_unsigned_type (type);
      else
	type = unsigned_type_node;
    }
  else if ((specbits & 1 << (int) RID_SIGNED)
	   && type == char_type_node)
    type = signed_char_type_node;
  else if (longlong)
    type = long_long_integer_type_node;
  else if (specbits & 1 << (int) RID_LONG)
    type = long_integer_type_node;
  else if (specbits & 1 << (int) RID_SHORT)
    type = short_integer_type_node;

  if (specbits & 1 << (int) RID_COMPLEX)
    {
      if (pedantic && !flag_isoc99)
	pedwarn ("ISO C89 does not support complex types");
      /* If we just have "complex", it is equivalent to
	 "complex double", but if any modifiers at all are specified it is
	 the complex form of TYPE.  E.g, "complex short" is
	 "complex short int".  */

      if (defaulted_int && ! longlong
	  && ! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
			    | (1 << (int) RID_SIGNED)
			    | (1 << (int) RID_UNSIGNED))))
	{
	  if (pedantic)
	    pedwarn ("ISO C does not support plain `complex' meaning `double complex'");
	  type = complex_double_type_node;
	}
      else if (type == integer_type_node)
	{
	  if (pedantic)
	    pedwarn ("ISO C does not support complex integer types");
	  type = complex_integer_type_node;
	}
      else if (type == float_type_node)
	type = complex_float_type_node;
      else if (type == double_type_node)
	type = complex_double_type_node;
      else if (type == long_double_type_node)
	type = complex_long_double_type_node;
      else
	{
	  if (pedantic)
	    pedwarn ("ISO C does not support complex integer types");
	  type = build_complex_type (type);
	}
    }

  /* Figure out the type qualifiers for the declaration.  There are
     two ways a declaration can become qualified.  One is something
     like `const int i' where the `const' is explicit.  Another is
     something like `typedef const int CI; CI i' where the type of the
     declaration contains the `const'.  */
  constp = !! (specbits & 1 << (int) RID_CONST) + TYPE_READONLY (type);
  restrictp = !! (specbits & 1 << (int) RID_RESTRICT) + TYPE_RESTRICT (type);
  volatilep = !! (specbits & 1 << (int) RID_VOLATILE) + TYPE_VOLATILE (type);
  inlinep = !! (specbits & (1 << (int) RID_INLINE));
  if (constp > 1 && ! flag_isoc99)
    pedwarn ("duplicate `const'");
  if (restrictp > 1 && ! flag_isoc99)
    pedwarn ("duplicate `restrict'");
  if (volatilep > 1 && ! flag_isoc99)
    pedwarn ("duplicate `volatile'");
  if (! flag_gen_aux_info && (TYPE_QUALS (type)))
    type = TYPE_MAIN_VARIANT (type);
  type_quals = ((constp ? TYPE_QUAL_CONST : 0)
		| (restrictp ? TYPE_QUAL_RESTRICT : 0)
		| (volatilep ? TYPE_QUAL_VOLATILE : 0));

  /* Warn if two storage classes are given. Default to `auto'.  */

  {
    int nclasses = 0;

    if (specbits & 1 << (int) RID_AUTO) nclasses++;
    if (specbits & 1 << (int) RID_STATIC) nclasses++;
    if (specbits & 1 << (int) RID_EXTERN) nclasses++;
    if (specbits & 1 << (int) RID_REGISTER) nclasses++;
    if (specbits & 1 << (int) RID_TYPEDEF) nclasses++;

    /* "static __thread" and "extern __thread" are allowed.  */
    if ((specbits & (1 << (int) RID_THREAD
		     | 1 << (int) RID_STATIC
		     | 1 << (int) RID_EXTERN)) == (1 << (int) RID_THREAD))
      nclasses++;

    /* Warn about storage classes that are invalid for certain
       kinds of declarations (parameters, typenames, etc.).  */

    if (nclasses > 1)
      error ("multiple storage classes in declaration of `%s'", name);
    else if (funcdef_flag
	     && (specbits
		 & ((1 << (int) RID_REGISTER)
		    | (1 << (int) RID_AUTO)
		    | (1 << (int) RID_TYPEDEF)
		    | (1 << (int) RID_THREAD))))
      {
	if (specbits & 1 << (int) RID_AUTO
	    && (pedantic || current_binding_level == global_binding_level))
	  pedwarn ("function definition declared `auto'");
	if (specbits & 1 << (int) RID_REGISTER)
	  error ("function definition declared `register'");
	if (specbits & 1 << (int) RID_TYPEDEF)
	  error ("function definition declared `typedef'");
	if (specbits & 1 << (int) RID_THREAD)
	  error ("function definition declared `__thread'");
	specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
		      | (1 << (int) RID_AUTO) | (1 << (int) RID_THREAD));
      }
    else if (decl_context != NORMAL && nclasses > 0)
      {
	if (decl_context == PARM && specbits & 1 << (int) RID_REGISTER)
	  ;
	else
	  {
	    switch (decl_context)
	      {
	      case FIELD:
		error ("storage class specified for structure field `%s'",
		       name);
		break;
	      case PARM:
		error ("storage class specified for parameter `%s'", name);
		break;
	      default:
		error ("storage class specified for typename");
		break;
	      }
	    specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
			  | (1 << (int) RID_AUTO) | (1 << (int) RID_STATIC)
			  | (1 << (int) RID_EXTERN) | (1 << (int) RID_THREAD));
	  }
      }
    else if (specbits & 1 << (int) RID_EXTERN && initialized && ! funcdef_flag)
      {
	/* `extern' with initialization is invalid if not at top level.  */
	if (current_binding_level == global_binding_level)
	  warning ("`%s' initialized and declared `extern'", name);
	else
	  error ("`%s' has both `extern' and initializer", name);
      }
    else if (current_binding_level == global_binding_level)
      {
	if (specbits & 1 << (int) RID_AUTO)
	  error ("top-level declaration of `%s' specifies `auto'", name);
      }
    else
      {
	if (specbits & 1 << (int) RID_EXTERN && funcdef_flag)
	  error ("nested function `%s' declared `extern'", name);
	else if ((specbits & (1 << (int) RID_THREAD
			       | 1 << (int) RID_EXTERN
			       | 1 << (int) RID_STATIC))
		 == (1 << (int) RID_THREAD))
	  {
	    error ("function-scope `%s' implicitly auto and declared `__thread'",
		   name);
	    specbits &= ~(1 << (int) RID_THREAD);
	  }
      }
  }

  /* Now figure out the structure of the declarator proper.
     Descend through it, creating more complex types, until we reach
     the declared identifier (or NULL_TREE, in an absolute declarator).  */

  while (declarator && TREE_CODE (declarator) != IDENTIFIER_NODE)
    {
      if (type == error_mark_node)
	{
	  declarator = TREE_OPERAND (declarator, 0);
	  continue;
	}

      /* Each level of DECLARATOR is either an ARRAY_REF (for ...[..]),
	 an INDIRECT_REF (for *...),
	 a CALL_EXPR (for ...(...)),
	 a TREE_LIST (for nested attributes),
	 an identifier (for the name being declared)
	 or a null pointer (for the place in an absolute declarator
	 where the name was omitted).
	 For the last two cases, we have just exited the loop.

	 At this point, TYPE is the type of elements of an array,
	 or for a function to return, or for a pointer to point to.
	 After this sequence of ifs, TYPE is the type of the
	 array or function or pointer, and DECLARATOR has had its
	 outermost layer removed.  */

      if (array_ptr_quals != NULL_TREE || array_parm_static)
	{
	  /* Only the innermost declarator (making a parameter be of
	     array type which is converted to pointer type)
	     may have static or type qualifiers.  */
	  error ("static or type qualifiers in non-parameter array declarator");
	  array_ptr_quals = NULL_TREE;
	  array_parm_static = 0;
	}

      if (TREE_CODE (declarator) == TREE_LIST)
	{
	  /* We encode a declarator with embedded attributes using
	     a TREE_LIST.  */
	  tree attrs = TREE_PURPOSE (declarator);
	  tree inner_decl;
	  int attr_flags = 0;
	  declarator = TREE_VALUE (declarator);
	  inner_decl = declarator;
	  while (inner_decl != NULL_TREE
		 && TREE_CODE (inner_decl) == TREE_LIST)
	    inner_decl = TREE_VALUE (inner_decl);
	  if (inner_decl == NULL_TREE
	      || TREE_CODE (inner_decl) == IDENTIFIER_NODE)
	    attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
	  else if (TREE_CODE (inner_decl) == CALL_EXPR)
	    attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
	  else if (TREE_CODE (inner_decl) == ARRAY_REF)
	    attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
	  returned_attrs = decl_attributes (&type,
					    chainon (returned_attrs, attrs),
					    attr_flags);
	}
      else if (TREE_CODE (declarator) == ARRAY_REF)
	{
	  tree itype = NULL_TREE;
	  tree size = TREE_OPERAND (declarator, 1);
	  /* The index is a signed object `sizetype' bits wide.  */
	  tree index_type = c_common_signed_type (sizetype);

	  array_ptr_quals = TREE_TYPE (declarator);
	  array_parm_static = TREE_STATIC (declarator);

	  declarator = TREE_OPERAND (declarator, 0);

	  /* Check for some types that there cannot be arrays of.  */

	  if (VOID_TYPE_P (type))
	    {
	      error ("declaration of `%s' as array of voids", name);
	      type = error_mark_node;
	    }

	  if (TREE_CODE (type) == FUNCTION_TYPE)
	    {
	      error ("declaration of `%s' as array of functions", name);
	      type = error_mark_node;
	    }

	  if (size == error_mark_node)
	    type = error_mark_node;

	  if (type == error_mark_node)
	    continue;

	  /* If size was specified, set ITYPE to a range-type for that size.
	     Otherwise, ITYPE remains null.  finish_decl may figure it out
	     from an initial value.  */

	  if (size)
	    {
	      /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue.  */
	      STRIP_TYPE_NOPS (size);

	      if (! INTEGRAL_TYPE_P (TREE_TYPE (size)))
		{
		  error ("size of array `%s' has non-integer type", name);
		  size = integer_one_node;
		}

	      if (pedantic && integer_zerop (size))
		pedwarn ("ISO C forbids zero-size array `%s'", name);

	      if (TREE_CODE (size) == INTEGER_CST)
		{
		  constant_expression_warning (size);
		  if (tree_int_cst_sgn (size) < 0)
		    {
		      error ("size of array `%s' is negative", name);
		      size = integer_one_node;
		    }
		}
	      else
		{
		  /* Make sure the array size remains visibly nonconstant
		     even if it is (eg) a const variable with known value.  */
		  size_varies = 1;

		  if (!flag_isoc99 && pedantic)
		    {
		      if (TREE_CONSTANT (size))
			pedwarn ("ISO C89 forbids array `%s' whose size can't be evaluated",
				 name);
		      else
			pedwarn ("ISO C89 forbids variable-size array `%s'",
				 name);
		    }
		}

	      if (integer_zerop (size))
		{
		  /* A zero-length array cannot be represented with an
		     unsigned index type, which is what we'll get with
		     build_index_type.  Create an open-ended range instead.  */
		  itype = build_range_type (sizetype, size, NULL_TREE);
		}
	      else
		{
		  /* Compute the maximum valid index, that is, size - 1.
		     Do the calculation in index_type, so that if it is
		     a variable the computations will be done in the
		     proper mode.  */
	          itype = fold (build (MINUS_EXPR, index_type,
				       convert (index_type, size),
				       convert (index_type, size_one_node)));

	          /* If that overflowed, the array is too big.
		     ??? While a size of INT_MAX+1 technically shouldn't
		     cause an overflow (because we subtract 1), the overflow
		     is recorded during the conversion to index_type, before
		     the subtraction.  Handling this case seems like an
		     unnecessary complication.  */
		  if (TREE_OVERFLOW (itype))
		    {
		      error ("size of array `%s' is too large", name);
		      type = error_mark_node;
		      continue;
		    }

		  if (size_varies)
		    itype = variable_size (itype);
		  itype = build_index_type (itype);
		}
	    }
	  else if (decl_context == FIELD)
	    {
	      if (pedantic && !flag_isoc99 && !in_system_header)
		pedwarn ("ISO C89 does not support flexible array members");

	      /* ISO C99 Flexible array members are effectively identical
		 to GCC's zero-length array extension.  */
	      itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
	    }

	  /* If pedantic, complain about arrays of incomplete types.  */

	  if (pedantic && !COMPLETE_TYPE_P (type))
	    pedwarn ("array type has incomplete element type");

#if 0
	  /* We shouldn't have a function type here at all!
	     Functions aren't allowed as array elements.  */
	  if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
	      && (constp || volatilep))
	    pedwarn ("ISO C forbids const or volatile function types");
#endif

	  /* Build the array type itself, then merge any constancy or
	     volatility into the target type.  We must do it in this order
	     to ensure that the TYPE_MAIN_VARIANT field of the array type
	     is set correctly.  */

	  type = build_array_type (type, itype);
	  if (type_quals)
	    type = c_build_qualified_type (type, type_quals);

	  if (size_varies)
	    C_TYPE_VARIABLE_SIZE (type) = 1;

	  /* The GCC extension for zero-length arrays differs from
	     ISO flexible array members in that sizeof yields zero.  */
	  if (size && integer_zerop (size))
	    {
	      layout_type (type);
	      TYPE_SIZE (type) = bitsize_zero_node;
	      TYPE_SIZE_UNIT (type) = size_zero_node;
	    }
	  if (decl_context != PARM
	      && (array_ptr_quals != NULL_TREE || array_parm_static))
	    {
	      error ("static or type qualifiers in non-parameter array declarator");
	      array_ptr_quals = NULL_TREE;
	      array_parm_static = 0;
	    }
	}
      else if (TREE_CODE (declarator) == CALL_EXPR)
	{
	  tree arg_types;

	  /* Declaring a function type.
	     Make sure we have a valid type for the function to return.  */
	  if (type == error_mark_node)
	    continue;

	  size_varies = 0;

	  /* Warn about some types functions can't return.  */

	  if (TREE_CODE (type) == FUNCTION_TYPE)
	    {
	      error ("`%s' declared as function returning a function", name);
	      type = integer_type_node;
	    }
	  if (TREE_CODE (type) == ARRAY_TYPE)
	    {
	      error ("`%s' declared as function returning an array", name);
	      type = integer_type_node;
	    }

	  /* Construct the function type and go to the next
	     inner layer of declarator.  */

	  arg_types = grokparms (TREE_OPERAND (declarator, 1),
				 funcdef_flag
				 /* Say it's a definition
				    only for the CALL_EXPR
				    closest to the identifier.  */
				 && TREE_CODE (TREE_OPERAND (declarator, 0)) == IDENTIFIER_NODE);
	  /* Type qualifiers before the return type of the function
	     qualify the return type, not the function type.  */
	  if (type_quals)
	    {
	      /* Type qualifiers on a function return type are normally
		 permitted by the standard but have no effect, so give a
		 warning at -W.  Qualifiers on a void return type have
		 meaning as a GNU extension, and are banned on function
		 definitions in ISO C.  FIXME: strictly we shouldn't
		 pedwarn for qualified void return types except on function
		 definitions, but not doing so could lead to the undesirable
		 state of a "volatile void" function return type not being
		 warned about, and a use of the function being compiled
		 with GNU semantics, with no diagnostics under -pedantic.  */
	      if (VOID_TYPE_P (type) && pedantic && !in_system_header)
		pedwarn ("ISO C forbids qualified void function return type");
	      else if (extra_warnings
		       && !(VOID_TYPE_P (type)
			    && type_quals == TYPE_QUAL_VOLATILE))
		warning ("type qualifiers ignored on function return type");

	      type = c_build_qualified_type (type, type_quals);
	    }
	  type_quals = TYPE_UNQUALIFIED;

	  type = build_function_type (type, arg_types);
	  declarator = TREE_OPERAND (declarator, 0);

	  /* Set the TYPE_CONTEXTs for each tagged type which is local to
	     the formal parameter list of this FUNCTION_TYPE to point to
	     the FUNCTION_TYPE node itself.  */

	  {
	    tree link;

	    for (link = last_function_parm_tags;
		 link;
		 link = TREE_CHAIN (link))
	      TYPE_CONTEXT (TREE_VALUE (link)) = type;
	  }
	}
      else if (TREE_CODE (declarator) == INDIRECT_REF)
	{
	  /* Merge any constancy or volatility into the target type
	     for the pointer.  */

	  if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
	      && type_quals)
	    pedwarn ("ISO C forbids qualified function types");
	  if (type_quals)
	    type = c_build_qualified_type (type, type_quals);
	  type_quals = TYPE_UNQUALIFIED;
	  size_varies = 0;

	  type = build_pointer_type (type);

	  /* Process a list of type modifier keywords
	     (such as const or volatile) that were given inside the `*'.  */

	  if (TREE_TYPE (declarator))