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The C and C++ Include Header Files

/usr/include/x86_64-linux-gnu/bits/iscanonical.h


$ cat -n /usr/include/x86_64-linux-gnu/bits/iscanonical.h

     1	/* Define iscanonical macro.  ldbl-96 version.
     2	   Copyright (C) 2016-2024 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	
    23	extern 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)).  */
    46	extern "C++" {
    47	inline int iscanonical (float __val) { return __iscanonicalf (__val); }
    48	inline int iscanonical (double __val) { return __iscanonical (__val); }
    49	inline int iscanonical (long double __val) { return __iscanonicall (__val); }
    50	# if __HAVE_DISTINCT_FLOAT128
    51	inline int iscanonical (_Float128 __val) { return __iscanonicalf128 (__val); }
    52	# endif
    53	}
    54	#endif /* __cplusplus */