llvm-project/clang/lib/Headers/limits.h

123 lines
3.4 KiB
C

/*===---- limits.h - Standard header for integer sizes --------------------===*\
*
* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
* See https://llvm.org/LICENSE.txt for license information.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*
\*===----------------------------------------------------------------------===*/
#ifndef __CLANG_LIMITS_H
#define __CLANG_LIMITS_H
/* The system's limits.h may, in turn, try to #include_next GCC's limits.h.
Avert this #include_next madness. */
#if defined __GNUC__ && !defined _GCC_LIMITS_H_
#define _GCC_LIMITS_H_
#endif
/* System headers include a number of constants from POSIX in <limits.h>.
Include it if we're hosted. */
#if __STDC_HOSTED__ && __has_include_next(<limits.h>)
#include_next <limits.h>
#endif
/* Many system headers try to "help us out" by defining these. No really, we
know how big each datatype is. */
#undef SCHAR_MIN
#undef SCHAR_MAX
#undef UCHAR_MAX
#undef SHRT_MIN
#undef SHRT_MAX
#undef USHRT_MAX
#undef INT_MIN
#undef INT_MAX
#undef UINT_MAX
#undef LONG_MIN
#undef LONG_MAX
#undef ULONG_MAX
#undef CHAR_BIT
#undef CHAR_MIN
#undef CHAR_MAX
/* C90/99 5.2.4.2.1 */
#define SCHAR_MAX __SCHAR_MAX__
#define SHRT_MAX __SHRT_MAX__
#define INT_MAX __INT_MAX__
#define LONG_MAX __LONG_MAX__
#define SCHAR_MIN (-__SCHAR_MAX__-1)
#define SHRT_MIN (-__SHRT_MAX__ -1)
#define INT_MIN (-__INT_MAX__ -1)
#define LONG_MIN (-__LONG_MAX__ -1L)
#define UCHAR_MAX (__SCHAR_MAX__*2 +1)
#define USHRT_MAX (__SHRT_MAX__ *2 +1)
#define UINT_MAX (__INT_MAX__ *2U +1U)
#define ULONG_MAX (__LONG_MAX__ *2UL+1UL)
#ifndef MB_LEN_MAX
#define MB_LEN_MAX 1
#endif
#define CHAR_BIT __CHAR_BIT__
/* C2x 5.2.4.2.1 */
/* FIXME: This is using the placeholder dates Clang produces for these macros
in C2x mode; switch to the correct values once they've been published. */
#if __STDC_VERSION__ >= 202000L
#define BOOL_WIDTH __BOOL_WIDTH__
#define CHAR_WIDTH CHAR_BIT
#define SCHAR_WIDTH CHAR_BIT
#define UCHAR_WIDTH CHAR_BIT
#define USHRT_WIDTH __SHRT_WIDTH__
#define SHRT_WIDTH __SHRT_WIDTH__
#define UINT_WIDTH __INT_WIDTH__
#define INT_WIDTH __INT_WIDTH__
#define ULONG_WIDTH __LONG_WIDTH__
#define LONG_WIDTH __LONG_WIDTH__
#define ULLONG_WIDTH __LLONG_WIDTH__
#define LLONG_WIDTH __LLONG_WIDTH__
#define BITINT_MAXWIDTH __BITINT_MAXWIDTH__
#endif
#ifdef __CHAR_UNSIGNED__ /* -funsigned-char */
#define CHAR_MIN 0
#define CHAR_MAX UCHAR_MAX
#else
#define CHAR_MIN SCHAR_MIN
#define CHAR_MAX __SCHAR_MAX__
#endif
/* C99 5.2.4.2.1: Added long long.
C++11 18.3.3.2: same contents as the Standard C Library header <limits.h>.
*/
#if __STDC_VERSION__ >= 199901L || __cplusplus >= 201103L
#undef LLONG_MIN
#undef LLONG_MAX
#undef ULLONG_MAX
#define LLONG_MAX __LONG_LONG_MAX__
#define LLONG_MIN (-__LONG_LONG_MAX__-1LL)
#define ULLONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
#endif
/* LONG_LONG_MIN/LONG_LONG_MAX/ULONG_LONG_MAX are a GNU extension. It's too bad
that we don't have something like #pragma poison that could be used to
deprecate a macro - the code should just use LLONG_MAX and friends.
*/
#if defined(__GNU_LIBRARY__) ? defined(__USE_GNU) : !defined(__STRICT_ANSI__)
#undef LONG_LONG_MIN
#undef LONG_LONG_MAX
#undef ULONG_LONG_MAX
#define LONG_LONG_MAX __LONG_LONG_MAX__
#define LONG_LONG_MIN (-__LONG_LONG_MAX__-1LL)
#define ULONG_LONG_MAX (__LONG_LONG_MAX__*2ULL+1ULL)
#endif
#endif /* __CLANG_LIMITS_H */