/usr/aarch64-linux-gnu/include/bits/nan.h is in libc6-dev-arm64-cross 2.23-0ubuntu3cross1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 | /* `NAN' constant for IEEE 754 machines.
Copyright (C) 1992-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _MATH_H
# error "Never use <bits/nan.h> directly; include <math.h> instead."
#endif
/* IEEE Not A Number. */
#if __GNUC_PREREQ(3,3)
# define NAN (__builtin_nanf (""))
#elif defined __GNUC__
# define NAN \
(__extension__ \
((union { unsigned __l __attribute__ ((__mode__ (__SI__))); float __d; }) \
{ __l: 0x7fc00000UL }).__d)
#else
# include <endian.h>
# if __BYTE_ORDER == __BIG_ENDIAN
# define __qnan_bytes { 0x7f, 0xc0, 0, 0 }
# endif
# if __BYTE_ORDER == __LITTLE_ENDIAN
# define __qnan_bytes { 0, 0, 0xc0, 0x7f }
# endif
static union { unsigned char __c[4]; float __d; } __qnan_union
__attribute__ ((__unused__)) = { __qnan_bytes };
# define NAN (__qnan_union.__d)
#endif /* GCC. */
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