diff options
Diffstat (limited to 'gnulib-m4/isnanf.m4')
| -rw-r--r-- | gnulib-m4/isnanf.m4 | 45 |
1 files changed, 5 insertions, 40 deletions
diff --git a/gnulib-m4/isnanf.m4 b/gnulib-m4/isnanf.m4 index c71e40fd..a23b22b1 100644 --- a/gnulib-m4/isnanf.m4 +++ b/gnulib-m4/isnanf.m4 @@ -1,9 +1,10 @@ # isnanf.m4 -# serial 21 -dnl Copyright (C) 2007-2024 Free Software Foundation, Inc. +# serial 22 +dnl Copyright (C) 2007-2025 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. +dnl This file is offered as-is, without any warranty. dnl Check how to get or define isnanf(). @@ -114,9 +115,7 @@ AC_DEFUN([gl_HAVE_ISNANF_IN_LIBM], ]) ]) -dnl Test whether isnanf() rejects Infinity (this fails on Solaris 2.5.1), -dnl recognizes a NaN (this fails on IRIX 6.5 with cc), and recognizes a NaN -dnl with in-memory representation 0x7fbfffff (this fails on IRIX 6.5). +dnl Test whether isnanf() rejects Infinity (this fails on Solaris 2.5.1). AC_DEFUN([gl_ISNANF_WORKS], [ AC_REQUIRE([AC_PROG_CC]) @@ -134,20 +133,6 @@ AC_DEFUN([gl_ISNANF_WORKS], # undef isnanf # define isnanf(x) isnan ((float)(x)) #endif -/* 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 -#define NWORDS \ - ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) -typedef union { unsigned int word[NWORDS]; float value; } memory_float; int main() { int result = 0; @@ -155,32 +140,12 @@ int main() if (isnanf (1.0f / 0.0f)) result |= 1; - if (!isnanf (NaN ())) - result |= 2; - -#if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT - /* The isnanf function should be immune against changes in the sign bit and - in the mantissa bits. The xor operation twiddles a bit that can only be - a sign bit or a mantissa bit. */ - if (FLT_EXPBIT0_WORD == 0 && FLT_EXPBIT0_BIT > 0) - { - memory_float m; - - m.value = NaN (); - /* Set the bits below the exponent to 01111...111. */ - m.word[0] &= -1U << FLT_EXPBIT0_BIT; - m.word[0] |= (1U << (FLT_EXPBIT0_BIT - 1)) - 1; - if (!isnanf (m.value)) - result |= 4; - } -#endif - return result; }]])], [gl_cv_func_isnanf_works=yes], [gl_cv_func_isnanf_works=no], [case "$host_os" in - irix* | solaris*) gl_cv_func_isnanf_works="guessing no" ;; + solaris*) gl_cv_func_isnanf_works="guessing no" ;; mingw* | windows*) # Guess yes on mingw, no on MSVC. AC_EGREP_CPP([Known], [ #ifdef __MINGW32__ |