clang  6.0.0svn
limits.h
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1 /*===---- limits.h - Standard header for integer sizes --------------------===*\
2  *
3  * Copyright (c) 2009 Chris Lattner
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a copy
6  * of this software and associated documentation files (the "Software"), to deal
7  * in the Software without restriction, including without limitation the rights
8  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9  * copies of the Software, and to permit persons to whom the Software is
10  * furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21  * THE SOFTWARE.
22  *
23 \*===----------------------------------------------------------------------===*/
24 
25 #ifndef __CLANG_LIMITS_H
26 #define __CLANG_LIMITS_H
27 
28 /* The system's limits.h may, in turn, try to #include_next GCC's limits.h.
29  Avert this #include_next madness. */
30 #if defined __GNUC__ && !defined _GCC_LIMITS_H_
31 #define _GCC_LIMITS_H_
32 #endif
33 
34 /* System headers include a number of constants from POSIX in <limits.h>.
35  Include it if we're hosted. */
36 #if __STDC_HOSTED__ && __has_include_next(<limits.h>)
37 #include_next <limits.h>
38 #endif
39 
40 /* Many system headers try to "help us out" by defining these. No really, we
41  know how big each datatype is. */
42 #undef SCHAR_MIN
43 #undef SCHAR_MAX
44 #undef UCHAR_MAX
45 #undef SHRT_MIN
46 #undef SHRT_MAX
47 #undef USHRT_MAX
48 #undef INT_MIN
49 #undef INT_MAX
50 #undef UINT_MAX
51 #undef LONG_MIN
52 #undef LONG_MAX
53 #undef ULONG_MAX
54 
55 #undef CHAR_BIT
56 #undef CHAR_MIN
57 #undef CHAR_MAX
58 
59 /* C90/99 5.2.4.2.1 */
60 #define SCHAR_MAX __SCHAR_MAX__
61 #define SHRT_MAX __SHRT_MAX__
62 #define INT_MAX __INT_MAX__
63 #define LONG_MAX __LONG_MAX__
64 
65 #define SCHAR_MIN (-__SCHAR_MAX__-1)
66 #define SHRT_MIN (-__SHRT_MAX__ -1)
67 #define INT_MIN (-__INT_MAX__ -1)
68 #define LONG_MIN (-__LONG_MAX__ -1L)
69 
70 #define UCHAR_MAX (__SCHAR_MAX__*2 +1)
71 #define USHRT_MAX (__SHRT_MAX__ *2 +1)
72 #define UINT_MAX (__INT_MAX__ *2U +1U)
73 #define ULONG_MAX (__LONG_MAX__ *2UL+1UL)
74 
75 #ifndef MB_LEN_MAX
76 #define MB_LEN_MAX 1
77 #endif
78 
79 #define CHAR_BIT __CHAR_BIT__
80 
81 #ifdef __CHAR_UNSIGNED__ /* -funsigned-char */
82 #define CHAR_MIN 0
83 #define CHAR_MAX UCHAR_MAX
84 #else
85 #define CHAR_MIN SCHAR_MIN
86 #define CHAR_MAX __SCHAR_MAX__
87 #endif
88 
89 /* C99 5.2.4.2.1: Added long long.
90  C++11 18.3.3.2: same contents as the Standard C Library header <limits.h>.
91  */
92 #if __STDC_VERSION__ >= 199901L || __cplusplus >= 201103L
93 
94 #undef LLONG_MIN
95 #undef LLONG_MAX
96 #undef ULLONG_MAX
97 
98 #define LLONG_MAX __LONG_LONG_MAX__
99 #define LLONG_MIN (-__LONG_LONG_MAX__-1LL)
100 #define ULLONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
101 #endif
102 
103 /* LONG_LONG_MIN/LONG_LONG_MAX/ULONG_LONG_MAX are a GNU extension. It's too bad
104  that we don't have something like #pragma poison that could be used to
105  deprecate a macro - the code should just use LLONG_MAX and friends.
106  */
107 #if defined(__GNU_LIBRARY__) ? defined(__USE_GNU) : !defined(__STRICT_ANSI__)
108 
109 #undef LONG_LONG_MIN
110 #undef LONG_LONG_MAX
111 #undef ULONG_LONG_MAX
112 
113 #define LONG_LONG_MAX __LONG_LONG_MAX__
114 #define LONG_LONG_MIN (-__LONG_LONG_MAX__-1LL)
115 #define ULONG_LONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
116 #endif
117 
118 #endif /* __CLANG_LIMITS_H */