gcc/config/darwin-c.c

   1 /* Darwin support needed only by C/C++ frontends.
   2    Copyright (C) 2001
   3    Free Software Foundation, Inc.
   4    Contributed by Apple Computer Inc.
   5
   6 This file is part of GNU CC.
   7
   8 GNU CC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2, or (at your option)
  11 any later version.
  12
  13 GNU CC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GNU CC; see the file COPYING.  If not, write to
  20 the Free Software Foundation, 59 Temple Place - Suite 330,
  21 Boston, MA 02111-1307, USA.  */
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "cpplib.h"
  26 #include "tree.h"
  27 #include "c-pragma.h"
  28 #include "c-lex.h"
  29 #include "c-tree.h"
  30 #include "toplev.h"
  31 #include "tm_p.h"
  32
  33 /* Pragmas.  */
  34
  35 #define BAD(msgid) do { warning (msgid); return; } while (0)
  36
  37 /* Maintain a small stack of alignments.  This is similar to pragma
  38    pack's stack, but simpler.  */
  39
  40 static void push_field_alignment PARAMS ((int));
  41 static void pop_field_alignment PARAMS ((void));
  42
  43 typedef struct align_stack
  44 {
  45   int alignment;
  46   struct align_stack * prev;
  47 } align_stack;
  48
  49 static struct align_stack * field_align_stack = NULL;
  50
  51 static void
  52 push_field_alignment (bit_alignment)
  53      int bit_alignment;
  54 {
  55   align_stack *entry = (align_stack *) xmalloc (sizeof (align_stack));
  56
  57   entry->alignment = maximum_field_alignment;
  58   entry->prev = field_align_stack;
  59   field_align_stack = entry;
  60
  61   maximum_field_alignment = bit_alignment;
  62 }
  63
  64 static void
  65 pop_field_alignment ()
  66 {
  67   if (field_align_stack)
  68     {
  69       align_stack *entry = field_align_stack;
  70
  71       maximum_field_alignment = entry->alignment;
  72       field_align_stack = entry->prev;
  73       free (entry);
  74     }
  75   else
  76     error ("too many #pragma options align=reset");
  77 }
  78
  79 /* Handlers for Darwin-specific pragmas.  */
  80
  81 void
  82 darwin_pragma_ignore (pfile)
  83      cpp_reader *pfile ATTRIBUTE_UNUSED;
  84 {
  85   /* Do nothing.  */
  86 }
  87
  88 /* #pragma options align={mac68k|power|reset} */
  89
  90 void
  91 darwin_pragma_options (pfile)
  92      cpp_reader *pfile ATTRIBUTE_UNUSED;
  93 {
  94   char *arg;
  95   tree t, x;
  96
  97   if (c_lex (&t) != CPP_NAME)
  98     BAD ("malformed '#pragma options', ignoring");
  99   arg = IDENTIFIER_POINTER (t);
 100   if (strcmp (arg, "align"))
 101     BAD ("malformed '#pragma options', ignoring");
 102   if (c_lex (&t) != CPP_EQ)
 103     BAD ("malformed '#pragma options', ignoring");
 104   if (c_lex (&t) != CPP_NAME)
 105     BAD ("malformed '#pragma options', ignoring");
 106
 107   if (c_lex (&x) != CPP_EOF)
 108     warning ("junk at end of '#pragma options'");
 109
 110   arg = IDENTIFIER_POINTER (t);
 111   if (!strcmp (arg, "mac68k"))
 112     push_field_alignment (16);
 113   else if (!strcmp (arg, "power"))
 114     push_field_alignment (0);
 115   else if (!strcmp (arg, "reset"))
 116     pop_field_alignment ();
 117   else
 118     warning ("malformed '#pragma options align={mac68k|power|reset}', ignoring");
 119 }
 120
 121 /* #pragma unused ([var {, var}*]) */
 122
 123 void
 124 darwin_pragma_unused (pfile)
 125      cpp_reader *pfile ATTRIBUTE_UNUSED;
 126 {
 127   tree decl, x;
 128   int tok;
 129
 130   if (c_lex (&x) != CPP_OPEN_PAREN)
 131     BAD ("missing '(' after '#pragma unused', ignoring");
 132
 133   while (1)
 134     {
 135       tok = c_lex (&decl);
 136       if (tok == CPP_NAME && decl)
 137         {
 138           tree local = IDENTIFIER_LOCAL_VALUE (decl);
 139           if (local && (TREE_CODE (local) == PARM_DECL
 140                         || TREE_CODE (local) == VAR_DECL))
 141             TREE_USED (local) = 1;
 142           tok = c_lex (&x);
 143           if (tok != CPP_COMMA)
 144             break;
 145         }
 146     }
 147
 148   if (tok != CPP_CLOSE_PAREN)
 149     BAD ("missing ')' after '#pragma unused', ignoring");
 150
 151   if (c_lex (&x) != CPP_EOF)
 152     warning ("junk at end of '#pragma unused'");
 153 }