1 /* Test of isnan() substitute.
2 Copyright (C) 2007 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
18 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */
28 #define ASSERT(expr) \
33 fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
39 /* The Compaq (ex-DEC) C 6.4 compiler chokes on the expression 0.0 / 0.0. */
44 static double zero = 0.0;
48 # define NaN() (0.0 / 0.0)
55 ASSERT (!isnan (3.141));
56 ASSERT (!isnan (3.141e30));
57 ASSERT (!isnan (3.141e-30));
58 ASSERT (!isnan (-2.718));
59 ASSERT (!isnan (-2.718e30));
60 ASSERT (!isnan (-2.718e-30));
61 /* Infinite values. */
62 ASSERT (!isnan (1.0 / 0.0));
63 ASSERT (!isnan (-1.0 / 0.0));
65 ASSERT (isnan (NaN ()));
66 #if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT
70 ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
71 typedef union { double value; unsigned int word[NWORDS]; } memory_double;
74 # if DBL_EXPBIT0_BIT > 0
75 m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1);
77 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
78 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
80 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)]
81 |= (unsigned int) 1 << DBL_EXPBIT0_BIT;
82 ASSERT (isnan (m.value));