1 /*
2 Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
3
4 Developed at SunPro, a Sun Microsystems, Inc. business.
5 Permission to use, copy, modify, and distribute this
6 software is freely granted, provided that this notice
7 is preserved.
8 */
9 /*
10 * nan () returns a nan.
11 * Added by Cygnus Support.
12 */
13
14 /*
15 FUNCTION
16 <<nan>>, <<nanf>>---representation of ``Not a Number''
17
18 INDEX
19 nan
20 INDEX
21 nanf
22
23 SYNOPSIS
24 #include <math.h>
25 double nan(const char *<[unused]>);
26 float nanf(const char *<[unused]>);
27
28
29 DESCRIPTION
30 <<nan>> and <<nanf>> return an IEEE NaN (Not a Number) in
31 double- and single-precision arithmetic respectively. The
32 argument is currently disregarded.
33
34 QUICKREF
35 nan - pure
36
37 */
38
39 #include "fdlibm.h"
40
41 #ifdef _NEED_FLOAT64
42
43 __float64
nan64(const char * unused)44 nan64(const char *unused)
45 {
46 __float64 x;
47
48 (void) unused;
49 #if __GNUC_PREREQ (3, 3)
50 x = __builtin_nan("");
51 #else
52 INSERT_WORDS(x,0x7ff80000,0);
53 #endif
54 return x;
55 }
56
57 _MATH_ALIAS_d_s(nan)
58
59 #endif /* _NEED_FLOAT64 */
60
