1 /**************************************************************************
2  *
3  * Copyright 2007-2013 VMware, Inc.
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 
28 #include "no_extern_c.h"
29 
30 #ifndef _C99_COMPAT_H_
31 #define _C99_COMPAT_H_
32 
33 
34 /*
35  * MSVC hacks.
36  */
37 #if defined(_MSC_VER)
38 
39 #  if _MSC_VER < 1800 || (_MSC_FULL_VER < 180031101 && !defined(__clang__))
40 #    error "Microsoft Visual Studio 2013 Update 4 or higher required"
41 #  endif
42 
43    /*
44     * Visual Studio will complain if we define the `inline` keyword, but
45     * actually it only supports the keyword on C++.
46     *
47     * To avoid this the _ALLOW_KEYWORD_MACROS must be set.
48     */
49 #  if !defined(_ALLOW_KEYWORD_MACROS)
50 #    define _ALLOW_KEYWORD_MACROS
51 #  endif
52 
53    /*
54     * XXX: MSVC has a `__restrict` keyword, but it also has a
55     * `__declspec(restrict)` modifier, so it is impossible to define a
56     * `restrict` macro without interfering with the latter.  Furthermore the
57     * MSVC standard library uses __declspec(restrict) under the _CRTRESTRICT
58     * macro.  For now resolve this issue by redefining _CRTRESTRICT, but going
59     * forward we should probably should stop using restrict, especially
60     * considering that our code does not obbey strict aliasing rules any way.
61     */
62 #  include <crtdefs.h>
63 #  undef _CRTRESTRICT
64 #  define _CRTRESTRICT
65 #endif
66 
67 
68 /*
69  * C99 inline keyword
70  */
71 #ifndef inline
72 #  ifdef __cplusplus
73      /* C++ supports inline keyword */
74 #  elif defined(__GNUC__)
75 #    define inline __inline__
76 #  elif defined(_MSC_VER)
77 #    define inline __inline
78 #  elif defined(__ICL)
79 #    define inline __inline
80 #  elif defined(__INTEL_COMPILER)
81      /* Intel compiler supports inline keyword */
82 #  elif defined(__WATCOMC__) && (__WATCOMC__ >= 1100)
83 #    define inline __inline
84 #  elif (__STDC_VERSION__ >= 199901L)
85      /* C99 supports inline keyword */
86 #  else
87 #    define inline
88 #  endif
89 #endif
90 
91 
92 /*
93  * C99 restrict keyword
94  *
95  * See also:
96  * - http://cellperformance.beyond3d.com/articles/2006/05/demystifying-the-restrict-keyword.html
97  */
98 #ifndef restrict
99 #  if (__STDC_VERSION__ >= 199901L)
100      /* C99 */
101 #  elif defined(__GNUC__)
102 #    define restrict __restrict__
103 #  elif defined(_MSC_VER)
104 #    define restrict __restrict
105 #  else
106 #    define restrict /* */
107 #  endif
108 #endif
109 
110 
111 /*
112  * C99 __func__ macro
113  */
114 #ifndef __func__
115 #  if (__STDC_VERSION__ >= 199901L)
116      /* C99 */
117 #  elif defined(__GNUC__)
118 #    define __func__ __FUNCTION__
119 #  elif defined(_MSC_VER)
120 #    define __func__ __FUNCTION__
121 #  else
122 #    define __func__ "<unknown>"
123 #  endif
124 #endif
125 
126 
127 /* Simple test case for debugging */
128 #if 0
129 static inline const char *
130 test_c99_compat_h(const void * restrict a,
131                   const void * restrict b)
132 {
133    return __func__;
134 }
135 #endif
136 
137 
138 /* Fallback definitions, for build systems other than autoconfig which don't
139  * auto-detect these things. */
140 #ifdef HAVE_NO_AUTOCONF
141 
142 #  ifndef _WIN32
143 #    define HAVE_PTHREAD
144 #    define HAVE_POSIX_MEMALIGN
145 #  endif
146 
147 #  ifdef __GNUC__
148 #    if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 2)
149 #      error "GCC version 4.2 or higher required"
150 #    endif
151 
152      /* https://gcc.gnu.org/onlinedocs/gcc-4.2.4/gcc/Other-Builtins.html */
153 #    define HAVE___BUILTIN_CLZ 1
154 #    define HAVE___BUILTIN_CLZLL 1
155 #    define HAVE___BUILTIN_CTZ 1
156 #    define HAVE___BUILTIN_EXPECT 1
157 #    define HAVE___BUILTIN_FFS 1
158 #    define HAVE___BUILTIN_FFSLL 1
159 #    define HAVE___BUILTIN_POPCOUNT 1
160 #    define HAVE___BUILTIN_POPCOUNTLL 1
161      /* https://gcc.gnu.org/onlinedocs/gcc-4.2.4/gcc/Function-Attributes.html */
162 #    define HAVE_FUNC_ATTRIBUTE_FLATTEN 1
163 #    define HAVE_FUNC_ATTRIBUTE_UNUSED 1
164 #    define HAVE_FUNC_ATTRIBUTE_FORMAT 1
165 #    define HAVE_FUNC_ATTRIBUTE_PACKED 1
166 #    define HAVE_FUNC_ATTRIBUTE_ALIAS 1
167 #    define HAVE_FUNC_ATTRIBUTE_NORETURN 1
168 
169 #    if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
170        /* https://gcc.gnu.org/onlinedocs/gcc-4.3.6/gcc/Other-Builtins.html */
171 #      define HAVE___BUILTIN_BSWAP32 1
172 #      define HAVE___BUILTIN_BSWAP64 1
173 #    endif
174 
175 #    if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
176 #      define HAVE___BUILTIN_UNREACHABLE 1
177 #    endif
178 
179 #  endif /* __GNUC__ */
180 
181 #endif /* !HAVE_AUTOCONF */
182 
183 
184 #endif /* _C99_COMPAT_H_ */
185