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