-# isfinite.m4 serial 3
-dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
+# isfinite.m4 serial 8
+dnl Copyright (C) 2007-2011 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.
AC_LIBOBJ([isfinite])
ISFINITE_LIBM=
fi
- AC_SUBST([REPLACE_ISFINITE])
AC_SUBST([ISFINITE_LIBM])
])
AC_DEFUN([gl_ISFINITEL_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
- AC_REQUIRE([AC_C_BIGENDIAN])
+ AC_REQUIRE([gl_BIGENDIAN])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether isfinite(long double) works], [gl_cv_func_isfinitel_works],
[
- AC_TRY_RUN([
+ AC_RUN_IFELSE([AC_LANG_SOURCE([[
#include <float.h>
#include <limits.h>
#include <math.h>
((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { unsigned int word[NWORDS]; long double value; }
memory_long_double;
+/* On Irix 6.5, gcc 3.4.3 can't compute compile-time NaN, and needs the
+ runtime type conversion. */
+#ifdef __sgi
+static long double NaNl ()
+{
+ double zero = 0.0;
+ return zero / zero;
+}
+#else
+# define NaNl() (0.0L / 0.0L)
+#endif
int main ()
{
- memory_long_double m;
- unsigned int i;
+ int result = 0;
- /* The isfinite macro 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 (since the exponent never extends to
- bit 31). */
- m.value = 0.0L / 0.0L;
- m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
- for (i = 0; i < NWORDS; i++)
- m.word[i] |= 1;
- if (isfinite (m.value))
- return 1;
+ {
+ memory_long_double m;
+ unsigned int i;
+
+ /* The isfinite macro 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 (since the exponent never extends to
+ bit 31). */
+ m.value = NaNl ();
+ m.word[NWORDS / 2] ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1);
+ for (i = 0; i < NWORDS; i++)
+ m.word[i] |= 1;
+ if (isfinite (m.value))
+ result |= 1;
+ }
#if ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_))
/* Representation of an 80-bit 'long double' as an initializer for a sequence
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0xC3333333, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ result |= 2;
}
{
/* Signalling NaN. */
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0x83333333, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ result |= 2;
}
/* The isfinite macro should recognize Pseudo-NaNs, Pseudo-Infinities,
Pseudo-Zeroes, Unnormalized Numbers, and Pseudo-Denormals, as defined in
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0x40000001, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ result |= 4;
}
{ /* Pseudo-Infinity. */
static memory_long_double x =
{ LDBL80_WORDS (0xFFFF, 0x00000000, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ result |= 8;
}
{ /* Pseudo-Zero. */
static memory_long_double x =
{ LDBL80_WORDS (0x4004, 0x00000000, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ result |= 16;
}
{ /* Unnormalized number. */
static memory_long_double x =
{ LDBL80_WORDS (0x4000, 0x63333333, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ result |= 32;
}
{ /* Pseudo-Denormal. */
static memory_long_double x =
{ LDBL80_WORDS (0x0000, 0x83333333, 0x00000000) };
if (isfinite (x.value))
- return 1;
+ return |= 64;
}
#endif
- return 0;
-}], [gl_cv_func_isfinitel_works=yes], [gl_cv_func_isfinitel_works=no],
+ return result;
+}]])], [gl_cv_func_isfinitel_works=yes], [gl_cv_func_isfinitel_works=no],
[case "$host_cpu" in
# Guess no on ia64, x86_64, i386.
ia64 | x86_64 | i*86) gl_cv_func_isnanl_works="guessing no";;