gcc/c-objc-common.c

   1 /* Some code common to C and ObjC front ends.
   2    Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007 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 3, 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 COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "tm.h"
  24 #include "tree.h"
  25 #include "rtl.h"
  26 #include "insn-config.h"
  27 #include "integrate.h"
  28 #include "c-tree.h"
  29 #include "c-pretty-print.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 "c-objc-common.h"
  41
  42 static bool c_tree_printer (pretty_printer *, text_info *, const char *,
  43                             int, bool, bool, bool);
  44
  45 bool
  46 c_missing_noreturn_ok_p (tree decl)
  47 {
  48   /* A missing noreturn is not ok for freestanding implementations and
  49      ok for the `main' function in hosted implementations.  */
  50   return flag_hosted && MAIN_NAME_P (DECL_ASSEMBLER_NAME (decl));
  51 }
  52
  53 /* We want to inline `extern inline' functions even if this would
  54    violate inlining limits.  Some glibc and linux constructs depend on
  55    such functions always being inlined when optimizing.  */
  56
  57 int
  58 c_disregard_inline_limits (tree fn)
  59 {
  60   if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) != NULL)
  61     return 1;
  62
  63   return (!flag_really_no_inline && DECL_DECLARED_INLINE_P (fn)
  64           && DECL_EXTERNAL (fn));
  65 }
  66
  67 int
  68 c_cannot_inline_tree_fn (tree *fnp)
  69 {
  70   tree fn = *fnp;
  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 (OPT_Winline, "function %q+F can never be inlined because it "
  81                  "is suppressed using -fno-inline", 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 (OPT_Winline, "function %q+F can never be inlined because it "
  91                  "might not be bound within this unit of translation", fn);
  92       goto cannot_inline;
  93     }
  94
  95   if (!function_attribute_inlinable_p (fn))
  96     {
  97       if (do_warning)
  98         warning (OPT_Winline, "function %q+F can never be inlined because it "
  99                  "uses attributes conflicting with inlining", fn);
 100       goto cannot_inline;
 101     }
 102
 103   return 0;
 104
 105  cannot_inline:
 106   DECL_UNINLINABLE (fn) = 1;
 107   return 1;
 108 }
 109
 110 /* Called from check_global_declarations.  */
 111
 112 bool
 113 c_warn_unused_global_decl (tree decl)
 114 {
 115   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
 116     return false;
 117   if (DECL_IN_SYSTEM_HEADER (decl))
 118     return false;
 119
 120   return true;
 121 }
 122
 123 /* Initialization common to C and Objective-C front ends.  */
 124 bool
 125 c_objc_common_init (void)
 126 {
 127   c_init_decl_processing ();
 128
 129   if (c_common_init () == false)
 130     return false;
 131
 132   /* These were not defined in the Objective-C front end, but I'm
 133      putting them here anyway.  The diagnostic format decoder might
 134      want an enhanced ObjC implementation.  */
 135   diagnostic_format_decoder (global_dc) = &c_tree_printer;
 136
 137   /* If still unspecified, make it match -std=c99
 138      (allowing for -pedantic-errors).  */
 139   if (mesg_implicit_function_declaration < 0)
 140     {
 141       if (flag_isoc99)
 142         mesg_implicit_function_declaration = flag_pedantic_errors ? 2 : 1;
 143       else
 144         mesg_implicit_function_declaration = 0;
 145     }
 146
 147   return true;
 148 }
 149
 150 /* Called during diagnostic message formatting process to print a
 151    source-level entity onto BUFFER.  The meaning of the format specifiers
 152    is as follows:
 153    %D: a general decl,
 154    %E: an identifier or expression,
 155    %F: a function declaration,
 156    %T: a type.
 157
 158    These format specifiers form a subset of the format specifiers set used
 159    by the C++ front-end.
 160    Please notice when called, the `%' part was already skipped by the
 161    diagnostic machinery.  */
 162 static bool
 163 c_tree_printer (pretty_printer *pp, text_info *text, const char *spec,
 164                 int precision, bool wide, bool set_locus, bool hash)
 165 {
 166   tree t = va_arg (*text->args_ptr, tree);
 167   tree name;
 168   const char *n = "({anonymous})";
 169   c_pretty_printer *cpp = (c_pretty_printer *) pp;
 170   pp->padding = pp_none;
 171
 172   if (precision != 0 || wide || hash)
 173     return false;
 174
 175   if (set_locus && text->locus)
 176     *text->locus = DECL_SOURCE_LOCATION (t);
 177
 178   switch (*spec)
 179     {
 180     case 'D':
 181       if (DECL_DEBUG_EXPR_IS_FROM (t) && DECL_DEBUG_EXPR (t))
 182         {
 183           t = DECL_DEBUG_EXPR (t);
 184           if (!DECL_P (t))
 185             {
 186               pp_c_expression (cpp, t);
 187               return true;
 188             }
 189         }
 190       /* FALLTHRU */
 191
 192     case 'F':
 193       if (DECL_NAME (t))
 194         n = lang_hooks.decl_printable_name (t, 2);
 195       break;
 196
 197     case 'T':
 198       gcc_assert (TYPE_P (t));
 199       name = TYPE_NAME (t);
 200
 201       if (name && TREE_CODE (name) == TYPE_DECL)
 202         {
 203           if (DECL_NAME (name))
 204             pp_string (cpp, lang_hooks.decl_printable_name (name, 2));
 205           else
 206             pp_type_id (cpp, t);
 207           return true;
 208         }
 209       else
 210         {
 211           pp_type_id (cpp, t);
 212           return true;
 213         }
 214       break;
 215
 216     case 'E':
 217       if (TREE_CODE (t) == IDENTIFIER_NODE)
 218         n = IDENTIFIER_POINTER (t);
 219       else
 220         {
 221           pp_expression (cpp, t);
 222           return true;
 223         }
 224       break;
 225
 226     default:
 227       return false;
 228     }
 229
 230   pp_string (cpp, n);
 231   return true;
 232 }
 233
 234 /* In C and ObjC, all decls have "C" linkage.  */
 235 bool
 236 has_c_linkage (tree decl ATTRIBUTE_UNUSED)
 237 {
 238   return true;
 239 }
 240
 241 void
 242 c_initialize_diagnostics (diagnostic_context *context)
 243 {
 244   pretty_printer *base = context->printer;
 245   c_pretty_printer *pp = XNEW (c_pretty_printer);
 246   memcpy (pp_base (pp), base, sizeof (pretty_printer));
 247   pp_c_pretty_printer_init (pp);
 248   context->printer = (pretty_printer *) pp;
 249
 250   /* It is safe to free this object because it was previously XNEW()'d.  */
 251   XDELETE (base);
 252 }
 253
 254 int
 255 c_types_compatible_p (tree x, tree y)
 256 {
 257     return comptypes (TYPE_MAIN_VARIANT (x), TYPE_MAIN_VARIANT (y));
 258 }
 259
 260 /* Determine if the type is a vla type for the backend.  */
 261
 262 bool
 263 c_vla_unspec_p (tree x, tree fn ATTRIBUTE_UNUSED)
 264 {
 265   return c_vla_type_p (x);
 266 }