-# isfinite.m4 serial 4
-dnl Copyright (C) 2007-2009 Free Software Foundation, Inc.
+# isfinite.m4 serial 7
+dnl Copyright (C) 2007-2010 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_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;
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.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;
#endif
return 0;
-}], [gl_cv_func_isfinitel_works=yes], [gl_cv_func_isfinitel_works=no],
+}]])], [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";;