aboutsummaryrefslogtreecommitdiffstats
path: root/include/c99_compat.h
blob: 24e96e0efefd2c5b6b041f5f40fabf0b87df891d (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
180
181
182
/**************************************************************************
 *
 * Copyright 2007-2013 VMware, Inc.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/

#include "no_extern_c.h"

#ifndef _C99_COMPAT_H_
#define _C99_COMPAT_H_


/*
 * MSVC hacks.
 */
#if defined(_MSC_VER)

#  if _MSC_VER < 1800 || (_MSC_FULL_VER < 180031101 && !defined(__clang__))
#    error "Microsoft Visual Studio 2013 Update 4 or higher required"
#  endif

   /*
    * Visual Studio will complain if we define the `inline` keyword, but
    * actually it only supports the keyword on C++.
    *
    * To avoid this the _ALLOW_KEYWORD_MACROS must be set.
    */
#  if !defined(_ALLOW_KEYWORD_MACROS)
#    define _ALLOW_KEYWORD_MACROS
#  endif

   /*
    * XXX: MSVC has a `__restrict` keyword, but it also has a
    * `__declspec(restrict)` modifier, so it is impossible to define a
    * `restrict` macro without interfering with the latter.  Furthermore the
    * MSVC standard library uses __declspec(restrict) under the _CRTRESTRICT
    * macro.  For now resolve this issue by redefining _CRTRESTRICT, but going
    * forward we should probably should stop using restrict, especially
    * considering that our code does not obbey strict aliasing rules any way.
    */
#  include <crtdefs.h>
#  undef _CRTRESTRICT
#  define _CRTRESTRICT
#endif


/*
 * C99 inline keyword
 */
#ifndef inline
#  ifdef __cplusplus
     /* C++ supports inline keyword */
#  elif defined(__GNUC__)
#    define inline __inline__
#  elif defined(_MSC_VER)
#    define inline __inline
#  elif defined(__ICL)
#    define inline __inline
#  elif defined(__INTEL_COMPILER)
     /* Intel compiler supports inline keyword */
#  elif defined(__WATCOMC__) && (__WATCOMC__ >= 1100)
#    define inline __inline
#  elif (__STDC_VERSION__ >= 199901L)
     /* C99 supports inline keyword */
#  else
#    define inline
#  endif
#endif


/*
 * C99 restrict keyword
 *
 * See also:
 * - http://cellperformance.beyond3d.com/articles/2006/05/demystifying-the-restrict-keyword.html
 */
#ifndef restrict
#  if (__STDC_VERSION__ >= 199901L)
     /* C99 */
#  elif defined(__GNUC__)
#    define restrict __restrict__
#  elif defined(_MSC_VER)
#    define restrict __restrict
#  else
#    define restrict /* */
#  endif
#endif


/*
 * C99 __func__ macro
 */
#ifndef __func__
#  if (__STDC_VERSION__ >= 199901L)
     /* C99 */
#  elif defined(__GNUC__)
#    define __func__ __FUNCTION__
#  elif defined(_MSC_VER)
#    define __func__ __FUNCTION__
#  else
#    define __func__ "<unknown>"
#  endif
#endif


/* Simple test case for debugging */
#if 0
static inline const char *
test_c99_compat_h(const void * restrict a,
                  const void * restrict b)
{
   return __func__;
}
#endif


/* Fallback definitions, for build systems other than autoconfig which don't
 * auto-detect these things. */
#ifdef HAVE_NO_AUTOCONF

#  ifndef _WIN32
#    define HAVE_PTHREAD
#    define HAVE_POSIX_MEMALIGN
#  endif

#  ifdef __GNUC__
#    if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 2)
#      error "GCC version 4.2 or higher required"
#    endif

     /* https://gcc.gnu.org/onlinedocs/gcc-4.2.4/gcc/Other-Builtins.html */
#    define HAVE___BUILTIN_CLZ 1
#    define HAVE___BUILTIN_CLZLL 1
#    define HAVE___BUILTIN_CTZ 1
#    define HAVE___BUILTIN_EXPECT 1
#    define HAVE___BUILTIN_FFS 1
#    define HAVE___BUILTIN_FFSLL 1
#    define HAVE___BUILTIN_POPCOUNT 1
#    define HAVE___BUILTIN_POPCOUNTLL 1
     /* https://gcc.gnu.org/onlinedocs/gcc-4.2.4/gcc/Function-Attributes.html */
#    define HAVE_FUNC_ATTRIBUTE_FLATTEN 1
#    define HAVE_FUNC_ATTRIBUTE_UNUSED 1
#    define HAVE_FUNC_ATTRIBUTE_FORMAT 1
#    define HAVE_FUNC_ATTRIBUTE_PACKED 1

#    if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
       /* https://gcc.gnu.org/onlinedocs/gcc-4.3.6/gcc/Other-Builtins.html */
#      define HAVE___BUILTIN_BSWAP32 1
#      define HAVE___BUILTIN_BSWAP64 1
#    endif

#    if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
#      define HAVE___BUILTIN_UNREACHABLE 1
#    endif

#  endif /* __GNUC__ */

#endif /* !HAVE_AUTOCONF */


#endif /* _C99_COMPAT_H_ */