clang 20.0.0git
limits.h
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1/*===---- limits.h - Standard header for integer sizes --------------------===*\
2 *
3 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 * See https://llvm.org/LICENSE.txt for license information.
5 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 *
7\*===----------------------------------------------------------------------===*/
8
9#ifndef __CLANG_LIMITS_H
10#define __CLANG_LIMITS_H
11
12#if defined(__MVS__) && __has_include_next(<limits.h>)
13#include_next <limits.h>
14#else
15
16/* The system's limits.h may, in turn, try to #include_next GCC's limits.h.
17 Avert this #include_next madness. */
18#if defined __GNUC__ && !defined _GCC_LIMITS_H_
19#define _GCC_LIMITS_H_
20#endif
21
22/* System headers include a number of constants from POSIX in <limits.h>.
23 Include it if we're hosted. */
24#if __STDC_HOSTED__ && __has_include_next(<limits.h>)
25#include_next <limits.h>
26#endif
27
28/* Many system headers try to "help us out" by defining these. No really, we
29 know how big each datatype is. */
30#undef SCHAR_MIN
31#undef SCHAR_MAX
32#undef UCHAR_MAX
33#undef SHRT_MIN
34#undef SHRT_MAX
35#undef USHRT_MAX
36#undef INT_MIN
37#undef INT_MAX
38#undef UINT_MAX
39#undef LONG_MIN
40#undef LONG_MAX
41#undef ULONG_MAX
42
43#undef CHAR_BIT
44#undef CHAR_MIN
45#undef CHAR_MAX
46
47/* C90/99 5.2.4.2.1 */
48#define SCHAR_MAX __SCHAR_MAX__
49#define SHRT_MAX __SHRT_MAX__
50#define INT_MAX __INT_MAX__
51#define LONG_MAX __LONG_MAX__
52
53#define SCHAR_MIN (-__SCHAR_MAX__-1)
54#define SHRT_MIN (-__SHRT_MAX__ -1)
55#define INT_MIN (-__INT_MAX__ -1)
56#define LONG_MIN (-__LONG_MAX__ -1L)
57
58#define UCHAR_MAX (__SCHAR_MAX__*2 +1)
59#if __SHRT_WIDTH__ < __INT_WIDTH__
60#define USHRT_MAX (__SHRT_MAX__ * 2 + 1)
61#else
62#define USHRT_MAX (__SHRT_MAX__ * 2U + 1U)
63#endif
64#define UINT_MAX (__INT_MAX__ *2U +1U)
65#define ULONG_MAX (__LONG_MAX__ *2UL+1UL)
66
67#ifndef MB_LEN_MAX
68#define MB_LEN_MAX 1
69#endif
70
71#define CHAR_BIT __CHAR_BIT__
72
73/* C23 5.2.4.2.1 */
74#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
75#define BOOL_WIDTH __BOOL_WIDTH__
76#define CHAR_WIDTH CHAR_BIT
77#define SCHAR_WIDTH CHAR_BIT
78#define UCHAR_WIDTH CHAR_BIT
79#define USHRT_WIDTH __SHRT_WIDTH__
80#define SHRT_WIDTH __SHRT_WIDTH__
81#define UINT_WIDTH __INT_WIDTH__
82#define INT_WIDTH __INT_WIDTH__
83#define ULONG_WIDTH __LONG_WIDTH__
84#define LONG_WIDTH __LONG_WIDTH__
85#define ULLONG_WIDTH __LLONG_WIDTH__
86#define LLONG_WIDTH __LLONG_WIDTH__
87
88#define BITINT_MAXWIDTH __BITINT_MAXWIDTH__
89#endif
90
91#ifdef __CHAR_UNSIGNED__ /* -funsigned-char */
92#define CHAR_MIN 0
93#define CHAR_MAX UCHAR_MAX
94#else
95#define CHAR_MIN SCHAR_MIN
96#define CHAR_MAX __SCHAR_MAX__
97#endif
98
99/* C99 5.2.4.2.1: Added long long.
100 C++11 18.3.3.2: same contents as the Standard C Library header <limits.h>.
101 */
102#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
103 (defined(__cplusplus) && __cplusplus >= 201103L)
104
105#undef LLONG_MIN
106#undef LLONG_MAX
107#undef ULLONG_MAX
108
109#define LLONG_MAX __LONG_LONG_MAX__
110#define LLONG_MIN (-__LONG_LONG_MAX__-1LL)
111#define ULLONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
112#endif
113
114/* LONG_LONG_MIN/LONG_LONG_MAX/ULONG_LONG_MAX are a GNU extension. It's too bad
115 that we don't have something like #pragma poison that could be used to
116 deprecate a macro - the code should just use LLONG_MAX and friends.
117 */
118#if defined(__GNU_LIBRARY__) ? defined(__USE_GNU) : !defined(__STRICT_ANSI__)
119
120#undef LONG_LONG_MIN
121#undef LONG_LONG_MAX
122#undef ULONG_LONG_MAX
123
124#define LONG_LONG_MAX __LONG_LONG_MAX__
125#define LONG_LONG_MIN (-__LONG_LONG_MAX__-1LL)
126#define ULONG_LONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
127#endif
128
129#endif /* __MVS__ */
130#endif /* __CLANG_LIMITS_H */