gcc/c-objc-common.c

   1 /* Some code common to C and ObjC front ends.
   2    Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 2, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING.  If not, write to the Free
  18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "tree.h"
  26 #include "rtl.h"
  27 #include "insn-config.h"
  28 #include "integrate.h"
  29 #include "c-tree.h"
  30 #include "function.h"
  31 #include "flags.h"
  32 #include "toplev.h"
  33 #include "diagnostic.h"
  34 #include "tree-inline.h"
  35 #include "varray.h"
  36 #include "ggc.h"
  37 #include "langhooks.h"
  38 #include "tree-mudflap.h"
  39 #include "target.h"
  40 #include "cgraph.h"
  41
  42 static bool c_tree_printer (pretty_printer *, text_info *);
  43
  44 bool
  45 c_missing_noreturn_ok_p (tree decl)
  46 {
  47   /* A missing noreturn is not ok for freestanding implementations and
  48      ok for the `main' function in hosted implementations.  */
  49   return flag_hosted && MAIN_NAME_P (DECL_ASSEMBLER_NAME (decl));
  50 }
  51
  52 /* We want to inline `extern inline' functions even if this would
  53    violate inlining limits.  Some glibc and linux constructs depend on
  54    such functions always being inlined when optimizing.  */
  55
  56 int
  57 c_disregard_inline_limits (tree fn)
  58 {
  59   if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) != NULL)
  60     return 1;
  61
  62   return (!flag_really_no_inline && DECL_DECLARED_INLINE_P (fn)
  63           && DECL_EXTERNAL (fn));
  64 }
  65
  66 int
  67 c_cannot_inline_tree_fn (tree *fnp)
  68 {
  69   tree fn = *fnp;
  70   tree t;
  71   bool do_warning = (warn_inline
  72                      && DECL_INLINE (fn)
  73                      && DECL_DECLARED_INLINE_P (fn)
  74                      && !DECL_IN_SYSTEM_HEADER (fn));
  75
  76   if (flag_really_no_inline
  77       && lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) == NULL)
  78     {
  79       if (do_warning)
  80         warning ("%Jfunction '%F' can never be inlined because it "
  81                  "is suppressed using -fno-inline", fn, fn);
  82       goto cannot_inline;
  83     }
  84
  85   /* Don't auto-inline anything that might not be bound within
  86      this unit of translation.  */
  87   if (!DECL_DECLARED_INLINE_P (fn) && !targetm.binds_local_p (fn))
  88     {
  89       if (do_warning)
  90         warning ("%Jfunction '%F' can never be inlined because it might not "
  91                  "be bound within this unit of translation", fn, fn);
  92       goto cannot_inline;
  93     }
  94
  95   if (! function_attribute_inlinable_p (fn))
  96     {
  97       if (do_warning)
  98         warning ("%Jfunction '%F' can never be inlined because it uses "
  99                  "attributes conflicting with inlining", fn, fn);
 100       goto cannot_inline;
 101     }
 102
 103   /* If a function has pending sizes, we must not defer its
 104      compilation, and we can't inline it as a tree.  */
 105   if (fn == current_function_decl)
 106     {
 107       t = get_pending_sizes ();
 108       put_pending_sizes (t);
 109
 110       if (t)
 111         {
 112           if (do_warning)
 113             warning ("%Jfunction '%F' can never be inlined because it has "
 114                      "pending sizes", fn, fn);
 115           goto cannot_inline;
 116         }
 117     }
 118
 119   if (! DECL_FILE_SCOPE_P (fn))
 120     {
 121       /* If a nested function has pending sizes, we may have already
 122          saved them.  */
 123       if (DECL_LANG_SPECIFIC (fn)->pending_sizes)
 124         {
 125           if (do_warning)
 126             warning ("%Jnested function '%F' can never be inlined because it "
 127                      "has possibly saved pending sizes", fn, fn);
 128           goto cannot_inline;
 129         }
 130     }
 131
 132   return 0;
 133
 134  cannot_inline:
 135   DECL_UNINLINABLE (fn) = 1;
 136   return 1;
 137 }
 138
 139 /* Called from check_global_declarations.  */
 140
 141 bool
 142 c_warn_unused_global_decl (tree decl)
 143 {
 144   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
 145     return false;
 146   if (DECL_IN_SYSTEM_HEADER (decl))
 147     return false;
 148
 149   return true;
 150 }
 151
 152 /* Initialization common to C and Objective-C front ends.  */
 153 bool
 154 c_objc_common_init (void)
 155 {
 156   static const enum tree_code stmt_codes[] = {
 157     c_common_stmt_codes
 158   };
 159
 160   INIT_STATEMENT_CODES (stmt_codes);
 161
 162   c_init_decl_processing ();
 163
 164   if (c_common_init () == false)
 165     return false;
 166
 167   /* These were not defined in the Objective-C front end, but I'm
 168      putting them here anyway.  The diagnostic format decoder might
 169      want an enhanced ObjC implementation.  */
 170   diagnostic_format_decoder (global_dc) = &c_tree_printer;
 171
 172   /* If still unspecified, make it match -std=c99
 173      (allowing for -pedantic-errors).  */
 174   if (mesg_implicit_function_declaration < 0)
 175     {
 176       if (flag_isoc99)
 177         mesg_implicit_function_declaration = flag_pedantic_errors ? 2 : 1;
 178       else
 179         mesg_implicit_function_declaration = 0;
 180     }
 181
 182   return true;
 183 }
 184
 185 /* Synthesize a function which calls all the global ctors or global dtors
 186    in this file.  */
 187
 188 static void
 189 build_cdtor (int method_type, tree cdtors)
 190 {
 191   tree body;
 192
 193   body = push_stmt_list ();
 194
 195   for (; cdtors; cdtors = TREE_CHAIN (cdtors))
 196     add_stmt (build_function_call (TREE_VALUE (cdtors), NULL_TREE));
 197
 198   body = pop_stmt_list (body);
 199
 200   cgraph_build_static_cdtor (method_type, body);
 201 }
 202
 203 /* Called at end of parsing, but before end-of-file processing.  */
 204
 205 void
 206 c_objc_common_finish_file (void)
 207 {
 208   if (pch_file)
 209     c_common_write_pch ();
 210
 211   if (static_ctors)
 212     {
 213       build_cdtor ('I', static_ctors);
 214       static_ctors = 0;
 215     }
 216   if (static_dtors)
 217     {
 218       build_cdtor ('D', static_dtors);
 219       static_dtors = 0;
 220     }
 221
 222   cgraph_finalize_compilation_unit ();
 223   cgraph_optimize ();
 224
 225   if (flag_mudflap)
 226     mudflap_finish_file ();
 227 }
 228
 229 /* Called during diagnostic message formatting process to print a
 230    source-level entity onto BUFFER.  The meaning of the format specifiers
 231    is as follows:
 232    %D: a general decl,
 233    %E: An expression,
 234    %F: a function declaration,
 235    %T: a type.
 236
 237    These format specifiers form a subset of the format specifiers set used
 238    by the C++ front-end.
 239    Please notice when called, the `%' part was already skipped by the
 240    diagnostic machinery.  */
 241 static bool
 242 c_tree_printer (pretty_printer *pp, text_info *text)
 243 {
 244   tree t = va_arg (*text->args_ptr, tree);
 245   const char *n = "({anonymous})";
 246
 247   switch (*text->format_spec)
 248     {
 249     case 'D':
 250     case 'F':
 251       if (DECL_NAME (t))
 252         n = lang_hooks.decl_printable_name (t, 2);
 253       break;
 254
 255     case 'T':
 256       if (TYPE_P (t))
 257         t = TYPE_NAME (t);
 258       if (t && TREE_CODE (t) == TYPE_DECL)
 259         {
 260           if (DECL_NAME (t))
 261             n = lang_hooks.decl_printable_name (t, 2);
 262         }
 263       else if (t)
 264         n = IDENTIFIER_POINTER (t);
 265       break;
 266
 267     case 'E':
 268       if (TREE_CODE (t) == IDENTIFIER_NODE)
 269         n = IDENTIFIER_POINTER (t);
 270       else
 271         return false;
 272       break;
 273
 274     default:
 275       return false;
 276     }
 277
 278   pp_string (pp, n);
 279   return true;
 280 }
 281
 282 tree
 283 c_objc_common_truthvalue_conversion (tree expr)
 284 {
 285  retry:
 286   switch (TREE_CODE (TREE_TYPE (expr)))
 287     {
 288     case ARRAY_TYPE:
 289       expr = default_conversion (expr);
 290       if (TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
 291         goto retry;
 292
 293       error ("used array that cannot be converted to pointer where scalar is required");
 294       return error_mark_node;
 295
 296     case RECORD_TYPE:
 297       error ("used struct type value where scalar is required");
 298       return error_mark_node;
 299
 300     case UNION_TYPE:
 301       error ("used union type value where scalar is required");
 302       return error_mark_node;
 303     default:
 304       break;
 305     }
 306
 307   return c_common_truthvalue_conversion (expr);
 308 }
 309
 310 /* In C and ObjC, all decls have "C" linkage.  */
 311 bool
 312 has_c_linkage (tree decl ATTRIBUTE_UNUSED)
 313 {
 314   return true;
 315 }