clang 19.0.0git
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/* The system's limits.h may, in turn, try to #include_next GCC's limits.h.
13 Avert this #include_next madness. */
14#if defined __GNUC__ && !defined _GCC_LIMITS_H_
15#define _GCC_LIMITS_H_
16#endif
17
18/* System headers include a number of constants from POSIX in <limits.h>.
19 Include it if we're hosted. */
20#if __STDC_HOSTED__ && __has_include_next(<limits.h>)
21#include_next <limits.h>
22#endif
23
24/* Many system headers try to "help us out" by defining these. No really, we
25 know how big each datatype is. */
26#undef SCHAR_MIN
27#undef SCHAR_MAX
28#undef UCHAR_MAX
29#undef SHRT_MIN
30#undef SHRT_MAX
31#undef USHRT_MAX
32#undef INT_MIN
33#undef INT_MAX
34#undef UINT_MAX
35#undef LONG_MIN
36#undef LONG_MAX
37#undef ULONG_MAX
38
39#undef CHAR_BIT
40#undef CHAR_MIN
41#undef CHAR_MAX
42
43/* C90/99 5.2.4.2.1 */
44#define SCHAR_MAX __SCHAR_MAX__
45#define SHRT_MAX __SHRT_MAX__
46#define INT_MAX __INT_MAX__
47#define LONG_MAX __LONG_MAX__
48
49#define SCHAR_MIN (-__SCHAR_MAX__-1)
50#define SHRT_MIN (-__SHRT_MAX__ -1)
51#define INT_MIN (-__INT_MAX__ -1)
52#define LONG_MIN (-__LONG_MAX__ -1L)
53
54#define UCHAR_MAX (__SCHAR_MAX__*2 +1)
55#if __SHRT_WIDTH__ < __INT_WIDTH__
56#define USHRT_MAX (__SHRT_MAX__ * 2 + 1)
57#else
58#define USHRT_MAX (__SHRT_MAX__ * 2U + 1U)
59#endif
60#define UINT_MAX (__INT_MAX__ *2U +1U)
61#define ULONG_MAX (__LONG_MAX__ *2UL+1UL)
62
63#ifndef MB_LEN_MAX
64#define MB_LEN_MAX 1
65#endif
66
67#define CHAR_BIT __CHAR_BIT__
68
69/* C23 5.2.4.2.1 */
70#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
71#define BOOL_WIDTH __BOOL_WIDTH__
72#define CHAR_WIDTH CHAR_BIT
73#define SCHAR_WIDTH CHAR_BIT
74#define UCHAR_WIDTH CHAR_BIT
75#define USHRT_WIDTH __SHRT_WIDTH__
76#define SHRT_WIDTH __SHRT_WIDTH__
77#define UINT_WIDTH __INT_WIDTH__
78#define INT_WIDTH __INT_WIDTH__
79#define ULONG_WIDTH __LONG_WIDTH__
80#define LONG_WIDTH __LONG_WIDTH__
81#define ULLONG_WIDTH __LLONG_WIDTH__
82#define LLONG_WIDTH __LLONG_WIDTH__
83
84#define BITINT_MAXWIDTH __BITINT_MAXWIDTH__
85#endif
86
87#ifdef __CHAR_UNSIGNED__ /* -funsigned-char */
88#define CHAR_MIN 0
89#define CHAR_MAX UCHAR_MAX
90#else
91#define CHAR_MIN SCHAR_MIN
92#define CHAR_MAX __SCHAR_MAX__
93#endif
94
95/* C99 5.2.4.2.1: Added long long.
96 C++11 18.3.3.2: same contents as the Standard C Library header <limits.h>.
97 */
98#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \
99 (defined(__cplusplus) && __cplusplus >= 201103L)
100
101#undef LLONG_MIN
102#undef LLONG_MAX
103#undef ULLONG_MAX
104
105#define LLONG_MAX __LONG_LONG_MAX__
106#define LLONG_MIN (-__LONG_LONG_MAX__-1LL)
107#define ULLONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
108#endif
109
110/* LONG_LONG_MIN/LONG_LONG_MAX/ULONG_LONG_MAX are a GNU extension. It's too bad
111 that we don't have something like #pragma poison that could be used to
112 deprecate a macro - the code should just use LLONG_MAX and friends.
113 */
114#if defined(__GNU_LIBRARY__) ? defined(__USE_GNU) : !defined(__STRICT_ANSI__)
115
116#undef LONG_LONG_MIN
117#undef LONG_LONG_MAX
118#undef ULONG_LONG_MAX
119
120#define LONG_LONG_MAX __LONG_LONG_MAX__
121#define LONG_LONG_MIN (-__LONG_LONG_MAX__-1LL)
122#define ULONG_LONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
123#endif
124
125#endif /* __CLANG_LIMITS_H */