gcc/c-lang.c

   1 /* Language-specific hook definitions for C front end.
   2    Copyright (C) 1991, 1995, 1997, 1998,
   3    1999, 2000, 2001 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "tree.h"
  26 #include "function.h"
  27 #include "input.h"
  28 #include "toplev.h"
  29 #include "diagnostic.h"
  30 #include "output.h"
  31 #include "flags.h"
  32 #include "ggc.h"
  33 #include "rtl.h"
  34 #include "expr.h"
  35 #include "c-tree.h"
  36 #include "c-lex.h"
  37 #include "cpplib.h"
  38
  39 static int c_tree_printer PARAMS ((output_buffer *));
  40 static int c_missing_noreturn_ok_p PARAMS ((tree));
  41 static void c_init PARAMS ((void));
  42 static void c_init_options PARAMS ((void));
  43 static void c_post_options PARAMS ((void));
  44
  45 /* Each front end provides its own.  */
  46 struct lang_hooks lang_hooks = {c_init,
  47                                 NULL, /* c_finish */
  48                                 c_init_options,
  49                                 c_decode_option,
  50                                 c_post_options};
  51
  52 /* Post-switch processing.  */
  53 static void
  54 c_post_options ()
  55 {
  56   cpp_post_options (parse_in);
  57 }
  58
  59 static void
  60 c_init_options ()
  61 {
  62   /* Make identifier nodes long enough for the language-specific slots.  */
  63   set_identifier_size (sizeof (struct lang_identifier));
  64
  65   parse_in = cpp_create_reader (ident_hash, CLK_GNUC89);
  66
  67   /* Mark as "unspecified".  */
  68   flag_bounds_check = -1;
  69 }
  70
  71 static void
  72 c_init ()
  73 {
  74   c_common_lang_init ();
  75
  76   /* If still unspecified, make it match -std=c99
  77      (allowing for -pedantic-errors).  */
  78   if (mesg_implicit_function_declaration < 0)
  79     {
  80       if (flag_isoc99)
  81         mesg_implicit_function_declaration = flag_pedantic_errors ? 2 : 1;
  82       else
  83         mesg_implicit_function_declaration = 0;
  84     }
  85
  86   save_lang_status = &push_c_function_context;
  87   restore_lang_status = &pop_c_function_context;
  88   mark_lang_status = &mark_c_function_context;
  89   lang_expand_expr = &c_expand_expr;
  90   lang_safe_from_p = &c_safe_from_p;
  91   diagnostic_format_decoder (global_dc) = &c_tree_printer;
  92   lang_expand_decl_stmt = &c_expand_decl_stmt;
  93   lang_missing_noreturn_ok_p = &c_missing_noreturn_ok_p;
  94
  95   c_parse_init ();
  96 }
  97
  98 const char *
  99 lang_identify ()
 100 {
 101   return "c";
 102 }
 103
 104 void
 105 print_lang_statistics ()
 106 {
 107 }
 108
 109 /* used by print-tree.c */
 110
 111 void
 112 lang_print_xnode (file, node, indent)
 113      FILE *file ATTRIBUTE_UNUSED;
 114      tree node ATTRIBUTE_UNUSED;
 115      int indent ATTRIBUTE_UNUSED;
 116 {
 117 }
 118
 119 /* Used by c-lex.c, but only for objc.  */
 120
 121 tree
 122 lookup_interface (arg)
 123      tree arg ATTRIBUTE_UNUSED;
 124 {
 125   return 0;
 126 }
 127
 128 tree
 129 is_class_name (arg)
 130     tree arg ATTRIBUTE_UNUSED;
 131 {
 132   return 0;
 133 }
 134
 135 void
 136 maybe_objc_check_decl (decl)
 137      tree decl ATTRIBUTE_UNUSED;
 138 {
 139 }
 140
 141 int
 142 maybe_objc_comptypes (lhs, rhs, reflexive)
 143      tree lhs ATTRIBUTE_UNUSED;
 144      tree rhs ATTRIBUTE_UNUSED;
 145      int reflexive ATTRIBUTE_UNUSED;
 146 {
 147   return -1;
 148 }
 149
 150 tree
 151 maybe_building_objc_message_expr ()
 152 {
 153   return 0;
 154 }
 155
 156 int
 157 recognize_objc_keyword ()
 158 {
 159   return 0;
 160 }
 161
 162 /* Used by c-typeck.c (build_external_ref), but only for objc.  */
 163
 164 tree
 165 lookup_objc_ivar (id)
 166      tree id ATTRIBUTE_UNUSED;
 167 {
 168   return 0;
 169 }
 170
 171 #if !defined(ASM_OUTPUT_CONSTRUCTOR) || !defined(ASM_OUTPUT_DESTRUCTOR)
 172 extern tree static_ctors;
 173 extern tree static_dtors;
 174
 175 static tree start_cdtor         PARAMS ((int));
 176 static void finish_cdtor        PARAMS ((tree));
 177
 178 static tree
 179 start_cdtor (method_type)
 180      int method_type;
 181 {
 182   tree fnname = get_file_function_name (method_type);
 183   tree void_list_node_1 = build_tree_list (NULL_TREE, void_type_node);
 184   tree body;
 185
 186   start_function (void_list_node_1,
 187                   build_nt (CALL_EXPR, fnname,
 188                             tree_cons (NULL_TREE, NULL_TREE, void_list_node_1),
 189                             NULL_TREE),
 190                   NULL_TREE);
 191   store_parm_decls ();
 192
 193   current_function_cannot_inline
 194     = "static constructors and destructors cannot be inlined";
 195
 196   body = c_begin_compound_stmt ();
 197
 198   pushlevel (0);
 199   clear_last_expr ();
 200   add_scope_stmt (/*begin_p=*/1, /*partial_p=*/0);
 201
 202   return body;
 203 }
 204
 205 static void
 206 finish_cdtor (body)
 207      tree body;
 208 {
 209   tree scope;
 210   tree block;
 211
 212   scope = add_scope_stmt (/*begin_p=*/0, /*partial_p=*/0);
 213   block = poplevel (0, 0, 0);
 214   SCOPE_STMT_BLOCK (TREE_PURPOSE (scope)) = block;
 215   SCOPE_STMT_BLOCK (TREE_VALUE (scope)) = block;
 216
 217   RECHAIN_STMTS (body, COMPOUND_BODY (body));
 218
 219   finish_function (0);
 220 }
 221 #endif
 222
 223 /* Called at end of parsing, but before end-of-file processing.  */
 224
 225 void
 226 finish_file ()
 227 {
 228 #ifndef ASM_OUTPUT_CONSTRUCTOR
 229   if (static_ctors)
 230     {
 231       tree body = start_cdtor ('I');
 232
 233       for (; static_ctors; static_ctors = TREE_CHAIN (static_ctors))
 234         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_ctors),
 235                                                  NULL_TREE));
 236
 237       finish_cdtor (body);
 238     }
 239 #endif
 240 #ifndef ASM_OUTPUT_DESTRUCTOR
 241   if (static_dtors)
 242     {
 243       tree body = start_cdtor ('D');
 244
 245       for (; static_dtors; static_dtors = TREE_CHAIN (static_dtors))
 246         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_dtors),
 247                                                  NULL_TREE));
 248
 249       finish_cdtor (body);
 250     }
 251 #endif
 252
 253   if (back_end_hook)
 254     (*back_end_hook) (getdecls ());
 255
 256   {
 257     int flags;
 258     FILE *stream = dump_begin (TDI_all, &flags);
 259
 260     if (stream)
 261       {
 262         dump_node (getdecls (), flags & ~TDF_SLIM, stream);
 263         dump_end (TDI_all, stream);
 264       }
 265   }
 266 }
 267
 268 /* Called during diagnostic message formatting process to print a
 269    source-level entity onto BUFFER.  The meaning of the format specifiers
 270    is as follows:
 271    %D: a general decl,
 272    %F: a function declaration,
 273    %T: a type.
 274
 275    These format specifiers form a subset of the format specifiers set used
 276    by the C++ front-end.
 277    Please notice when called, the `%' part was already skipped by the
 278    diagnostic machinery.  */
 279 static int
 280 c_tree_printer (buffer)
 281      output_buffer *buffer;
 282 {
 283   tree t = va_arg (output_buffer_format_args (buffer), tree);
 284
 285   switch (*output_buffer_text_cursor (buffer))
 286     {
 287     case 'D':
 288     case 'F':
 289     case 'T':
 290       {
 291         const char *n = DECL_NAME (t)
 292           ? (*decl_printable_name) (t, 2)
 293           : "({anonymous})";
 294         output_add_string (buffer, n);
 295       }
 296       return 1;
 297
 298     default:
 299       return 0;
 300     }
 301 }
 302
 303 static int
 304 c_missing_noreturn_ok_p (decl)
 305      tree decl;
 306 {
 307   /* A missing noreturn is not ok for freestanding implementations and
 308      ok for the `main' function in hosted implementations.  */
 309   return flag_hosted && MAIN_NAME_P (DECL_ASSEMBLER_NAME (decl));
 310 }