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 pedantic && -std=c99.  */
  74   if (mesg_implicit_function_declaration < 0)
  75     {
  76       if (pedantic && flag_isoc99)
  77         mesg_implicit_function_declaration = flag_pedantic_errors ? 2 : 1;
  78       else
  79         mesg_implicit_function_declaration = 0;
  80     }
  81
  82   save_lang_status = &push_c_function_context;
  83   restore_lang_status = &pop_c_function_context;
  84   mark_lang_status = &mark_c_function_context;
  85   lang_expand_expr = &c_expand_expr;
  86   lang_safe_from_p = &c_safe_from_p;
  87   lang_printer = &c_tree_printer;
  88   lang_expand_decl_stmt = &c_expand_decl_stmt;
  89   lang_missing_noreturn_ok_p = &c_missing_noreturn_ok_p;
  90
  91   c_parse_init ();
  92 }
  93
  94 const char *
  95 lang_identify ()
  96 {
  97   return "c";
  98 }
  99
 100 void
 101 print_lang_statistics ()
 102 {
 103 }
 104
 105 /* used by print-tree.c */
 106
 107 void
 108 lang_print_xnode (file, node, indent)
 109      FILE *file ATTRIBUTE_UNUSED;
 110      tree node ATTRIBUTE_UNUSED;
 111      int indent ATTRIBUTE_UNUSED;
 112 {
 113 }
 114
 115 /* Used by c-lex.c, but only for objc.  */
 116
 117 tree
 118 lookup_interface (arg)
 119      tree arg ATTRIBUTE_UNUSED;
 120 {
 121   return 0;
 122 }
 123
 124 tree
 125 is_class_name (arg)
 126     tree arg ATTRIBUTE_UNUSED;
 127 {
 128   return 0;
 129 }
 130
 131 void
 132 maybe_objc_check_decl (decl)
 133      tree decl ATTRIBUTE_UNUSED;
 134 {
 135 }
 136
 137 int
 138 maybe_objc_comptypes (lhs, rhs, reflexive)
 139      tree lhs ATTRIBUTE_UNUSED;
 140      tree rhs ATTRIBUTE_UNUSED;
 141      int reflexive ATTRIBUTE_UNUSED;
 142 {
 143   return -1;
 144 }
 145
 146 tree
 147 maybe_objc_method_name (decl)
 148     tree decl ATTRIBUTE_UNUSED;
 149 {
 150   return 0;
 151 }
 152
 153 tree
 154 maybe_building_objc_message_expr ()
 155 {
 156   return 0;
 157 }
 158
 159 int
 160 recognize_objc_keyword ()
 161 {
 162   return 0;
 163 }
 164
 165 /* Used by c-typeck.c (build_external_ref), but only for objc.  */
 166
 167 tree
 168 lookup_objc_ivar (id)
 169      tree id ATTRIBUTE_UNUSED;
 170 {
 171   return 0;
 172 }
 173
 174 #if !defined(ASM_OUTPUT_CONSTRUCTOR) || !defined(ASM_OUTPUT_DESTRUCTOR)
 175 extern tree static_ctors;
 176 extern tree static_dtors;
 177
 178 static tree start_cdtor         PARAMS ((int));
 179 static void finish_cdtor        PARAMS ((tree));
 180
 181 static tree
 182 start_cdtor (method_type)
 183      int method_type;
 184 {
 185   tree fnname = get_file_function_name (method_type);
 186   tree void_list_node_1 = build_tree_list (NULL_TREE, void_type_node);
 187   tree body;
 188
 189   start_function (void_list_node_1,
 190                   build_nt (CALL_EXPR, fnname,
 191                             tree_cons (NULL_TREE, NULL_TREE, void_list_node_1),
 192                             NULL_TREE),
 193                   NULL_TREE, NULL_TREE);
 194   store_parm_decls ();
 195
 196   current_function_cannot_inline
 197     = "static constructors and destructors cannot be inlined";
 198
 199   body = c_begin_compound_stmt ();
 200
 201   pushlevel (0);
 202   clear_last_expr ();
 203   add_scope_stmt (/*begin_p=*/1, /*partial_p=*/0);
 204
 205   return body;
 206 }
 207
 208 static void
 209 finish_cdtor (body)
 210      tree body;
 211 {
 212   tree scope;
 213   tree block;
 214
 215   scope = add_scope_stmt (/*begin_p=*/0, /*partial_p=*/0);
 216   block = poplevel (0, 0, 0);
 217   SCOPE_STMT_BLOCK (TREE_PURPOSE (scope)) = block;
 218   SCOPE_STMT_BLOCK (TREE_VALUE (scope)) = block;
 219
 220   RECHAIN_STMTS (body, COMPOUND_BODY (body));
 221
 222   finish_function (0);
 223 }
 224 #endif
 225
 226 /* Called at end of parsing, but before end-of-file processing.  */
 227
 228 void
 229 finish_file ()
 230 {
 231 #ifndef ASM_OUTPUT_CONSTRUCTOR
 232   if (static_ctors)
 233     {
 234       tree body = start_cdtor ('I');
 235
 236       for (; static_ctors; static_ctors = TREE_CHAIN (static_ctors))
 237         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_ctors),
 238                                                  NULL_TREE));
 239
 240       finish_cdtor (body);
 241     }
 242 #endif
 243 #ifndef ASM_OUTPUT_DESTRUCTOR
 244   if (static_dtors)
 245     {
 246       tree body = start_cdtor ('D');
 247
 248       for (; static_dtors; static_dtors = TREE_CHAIN (static_dtors))
 249         c_expand_expr_stmt (build_function_call (TREE_VALUE (static_dtors),
 250                                                  NULL_TREE));
 251
 252       finish_cdtor (body);
 253     }
 254 #endif
 255
 256   if (back_end_hook)
 257     (*back_end_hook) (getdecls ());
 258
 259   if (flag_dump_translation_unit)
 260     dump_node_to_file (getdecls (), flag_dump_translation_unit);
 261 }
 262
 263 /* Called during diagnostic message formatting process to print a
 264    source-level entity onto BUFFER.  The meaning of the format specifiers
 265    is as follows:
 266    %D: a general decl,
 267    %F: a function declaration,
 268    %T: a type.
 269
 270    These format specifiers form a subset of the format specifiers set used
 271    by the C++ front-end.
 272    Please notice when called, the `%' part was already skipped by the
 273    diagnostic machinery.  */
 274 static int
 275 c_tree_printer (buffer)
 276      output_buffer *buffer;
 277 {
 278   tree t = va_arg (output_buffer_format_args (buffer), tree);
 279
 280   switch (*output_buffer_text_cursor (buffer))
 281     {
 282     case 'D':
 283     case 'F':
 284     case 'T':
 285       {
 286         const char *n = DECL_NAME (t)
 287           ? (*decl_printable_name) (t, 2)
 288           : "({anonymous})";
 289         output_add_string (buffer, n);
 290       }
 291       return 1;
 292
 293     default:
 294       return 0;
 295     }
 296 }
 297
 298 static int
 299 c_missing_noreturn_ok_p (decl)
 300      tree decl;
 301 {
 302   /* A missing noreturn is not ok for freestanding implementations and
 303      ok for the `main' function in hosted implementations.  */
 304   return flag_hosted && MAIN_NAME_P (DECL_ASSEMBLER_NAME (decl));
 305 }