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/* Test of isnanf() substitute.
Copyright (C) 2007 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
#include <config.h>
#include "isnanf.h"
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#define ASSERT(expr) \
do \
{ \
if (!(expr)) \
{ \
fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
abort (); \
} \
} \
while (0)
/* The Compaq (ex-DEC) C 6.4 compiler chokes on the expression 0.0 / 0.0. */
#ifdef __DECC
static float
NaN ()
{
static float zero = 0.0f;
return zero / zero;
}
#else
# define NaN() (0.0f / 0.0f)
#endif
int
main ()
{
/* Finite values. */
ASSERT (!isnanf (3.141f));
ASSERT (!isnanf (3.141e30f));
ASSERT (!isnanf (3.141e-30f));
ASSERT (!isnanf (-2.718f));
ASSERT (!isnanf (-2.718e30f));
ASSERT (!isnanf (-2.718e-30f));
/* Infinite values. */
ASSERT (!isnanf (1.0f / 0.0f));
ASSERT (!isnanf (-1.0f / 0.0f));
/* Quiet NaN. */
ASSERT (isnanf (NaN ()));
#if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT
/* Signalling NaN. */
{
#define NWORDS \
((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { float value; unsigned int word[NWORDS]; } memory_float;
memory_float m;
m.value = NaN ();
# if FLT_EXPBIT0_BIT > 0
m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1);
# else
m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
# endif
if (FLT_EXPBIT0_WORD < NWORDS / 2)
m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT;
else
m.word[0] |= (unsigned int) 1;
ASSERT (isnanf (m.value));
}
#endif
return 0;
}
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