summaryrefslogtreecommitdiffstats
path: root/gcc/c-pragma.c
blob: a37aa98755f3ada8960b308a6eff8a7ce2b0d7db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/* Handle #pragma, system V.4 style.  Supports #pragma weak and #pragma pack.
   Copyright (C) 1992, 1997 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "config.h"
#include <stdio.h>
#include "tree.h"
#include "except.h"
#include "function.h"
#include "defaults.h"
#include "c-pragma.h"
#include "flags.h"

#ifdef HANDLE_SYSV_PRAGMA

/* When structure field packing is in effect, this variable is the
   number of bits to use as the maximum alignment.  When packing is not
   in effect, this is zero.  */

extern int maximum_field_alignment;

/* File used for outputting assembler code.  */
extern FILE *asm_out_file;

/* Handle one token of a pragma directive.  TOKEN is the
   current token, and STRING is its printable form.  */

void
handle_pragma_token (string, token)
     char *string;
     tree token;
{
  static enum pragma_state state = ps_start, type;
  static char *name;
  static char *value;
  static int align;

  if (string == 0)
    {
      if (type == ps_pack)
	{
	  if (state == ps_right)
	    maximum_field_alignment = align * 8;
	  else
	    warning ("malformed `#pragma pack'");
	}
      else if (type == ps_weak)
	{
#ifdef HANDLE_PRAGMA_WEAK
	  if (HANDLE_PRAGMA_WEAK)
	    handle_pragma_weak (state, name, value);

#endif /* HANDLE_PRAGMA_WEAK */
	}

      type = state = ps_start;
      return;
    }

  switch (state)
    {
    case ps_start:
      if (token && TREE_CODE (token) == IDENTIFIER_NODE)
	{
	  if (strcmp (IDENTIFIER_POINTER (token), "pack") == 0)
	    type = state = ps_pack;
	  else if (strcmp (IDENTIFIER_POINTER (token), "weak") == 0)
	    type = state = ps_weak;
	  else
	    {
	      type = state = ps_done;

	      /* Issue a warning message if we have been asked to do so.
		 Ignoring unknown pragmas in system header file unless          
		 an explcit -Wunknown-pragmas has been given. */                
	      if (warn_unknown_pragmas > 1
		  || (warn_unknown_pragmas && ! in_system_header))
		warning ("ignoring pragma: %s", string);
	    }
	}
      else
	type = state = ps_done;
      break;

    case ps_weak:
      if (token && TREE_CODE (token) == IDENTIFIER_NODE)
	{
	  name = IDENTIFIER_POINTER (token);
	  state = ps_name;
	}
      else
	state = ps_bad;
      break;

    case ps_name:
      state = (strcmp (string, "=") ? ps_bad : ps_equals);
      break;

    case ps_equals:
      if (token && TREE_CODE (token) == IDENTIFIER_NODE)
	{
	  value = IDENTIFIER_POINTER (token);
	  state = ps_value;
	}
      else
	state = ps_bad;
      break;

    case ps_value:
      state = ps_bad;
      break;

    case ps_pack:
      if (strcmp (string, "(") == 0)
	state = ps_left;
      else
	state = ps_bad;
      break;

    case ps_left:
      if (token && TREE_CODE (token) == INTEGER_CST
	  && TREE_INT_CST_HIGH (token) == 0)
	switch (TREE_INT_CST_LOW (token))
	  {
	  case 1:
	  case 2:
	  case 4:
	    align = TREE_INT_CST_LOW (token);
	    state = ps_align;
	    break;

	  default:
	    state = ps_bad;
	  }
      else if (! token && strcmp (string, ")") == 0)
	{
	  align = 0;
	  state = ps_right;
	}
      else
	state = ps_bad;
      break;

    case ps_align:
      if (strcmp (string, ")") == 0)
	state = ps_right;
      else
	state = ps_bad;
      break;

    case ps_right:
      state = ps_bad;
      break;

    case ps_bad:
    case ps_done:
      break;

    default:
      abort ();
    }
}
#endif /* HANDLE_SYSV_PRAGMA */
OpenPOWER on IntegriCloud