1/* Define iscanonical macro. ldbl-96 version.
2 Copyright (C) 2016-2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _MATH_H
20# error "Never use <bits/iscanonical.h> directly; include <math.h> instead."
21#endif
22
23extern int __iscanonicall (long double __x)
24 __THROW __attribute__ ((__const__));
25#define __iscanonicalf(x) ((void) (__typeof (x)) (x), 1)
26#define __iscanonical(x) ((void) (__typeof (x)) (x), 1)
27#if __HAVE_DISTINCT_FLOAT128
28# define __iscanonicalf128(x) ((void) (__typeof (x)) (x), 1)
29#endif
30
31/* Return nonzero value if X is canonical. In IEEE interchange binary
32 formats, all values are canonical, but the argument must still be
33 converted to its semantic type for any exceptions arising from the
34 conversion, before being discarded; in extended precision, there
35 are encodings that are not consistently handled as corresponding to
36 any particular value of the type, and we return 0 for those. */
37#ifndef __cplusplus
38# define iscanonical(x) __MATH_TG ((x), __iscanonical, (x))
39#else
40/* In C++ mode, __MATH_TG cannot be used, because it relies on
41 __builtin_types_compatible_p, which is a C-only builtin. On the
42 other hand, overloading provides the means to distinguish between
43 the floating-point types. The overloading resolution will match
44 the correct parameter (regardless of type qualifiers (i.e.: const
45 and volatile)). */
46extern "C++" {
47inline int iscanonical (float __val) { return __iscanonicalf (__val); }
48inline int iscanonical (double __val) { return __iscanonical (__val); }
49inline int iscanonical (long double __val) { return __iscanonicall (__val); }
50# if __HAVE_DISTINCT_FLOAT128
51inline int iscanonical (_Float128 __val) { return __iscanonicalf128 (__val); }
52# endif
53}
54#endif /* __cplusplus */
55

source code of include/x86_64-linux-gnu/bits/iscanonical.h