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-rw-r--r--m4/frexp.m425
1 files changed, 16 insertions, 9 deletions
diff --git a/m4/frexp.m4 b/m4/frexp.m4
index 2e0fb3b..2eb98a1 100644
--- a/m4/frexp.m4
+++ b/m4/frexp.m4
@@ -1,5 +1,5 @@
-# frexp.m4 serial 10
-dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
+# frexp.m4 serial 15
+dnl Copyright (C) 2007-2013 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.
@@ -44,8 +44,6 @@ AC_DEFUN([gl_FUNC_FREXP],
if test $gl_func_frexp = yes; then
AC_DEFINE([HAVE_FREXP], [1],
[Define if the frexp() function is available and works.])
- else
- AC_LIBOBJ([frexp])
fi
AC_SUBST([FREXP_LIBM])
])
@@ -68,8 +66,6 @@ AC_DEFUN([gl_FUNC_FREXP_NO_LIBM],
if test $gl_func_frexp_no_libm = yes; then
AC_DEFINE([HAVE_FREXP_IN_LIBC], [1],
[Define if the frexp() function is available in libc.])
- else
- AC_LIBOBJ([frexp])
fi
])
@@ -92,11 +88,12 @@ AC_DEFUN([gl_CHECK_FREXP_NO_LIBM],
dnl Test whether frexp() works also on denormalized numbers (this fails e.g. on
dnl NetBSD 3.0), on infinite numbers (this fails e.g. on IRIX 6.5 and mingw),
-dnl and on negative zero (this fails e.g. on NetBSD 4.99).
+dnl and on negative zero (this fails e.g. on NetBSD 4.99 and mingw).
AC_DEFUN([gl_FUNC_FREXP_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CHECK_DECLS_ONCE([alarm])
AC_CACHE_CHECK([whether frexp works], [gl_cv_func_frexp_works],
[
AC_RUN_IFELSE(
@@ -104,10 +101,14 @@ AC_DEFUN([gl_FUNC_FREXP_WORKS],
#include <float.h>
#include <math.h>
#include <string.h>
+#if HAVE_DECL_ALARM
+# include <signal.h>
+# include <unistd.h>
+#endif
/* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0.
ICC 10.0 has a bug when optimizing the expression -zero.
The expression -DBL_MIN * DBL_MIN does not work when cross-compiling
- to PowerPC on MacOS X 10.5. */
+ to PowerPC on Mac OS X 10.5. */
#if defined __hpux || defined __sgi || defined __ICC
static double
compute_minus_zero (void)
@@ -124,6 +125,12 @@ int main()
int i;
volatile double x;
double zero = 0.0;
+#if HAVE_DECL_ALARM
+ /* NeXTstep 3.3 frexp() runs into an endless loop when called on an infinite
+ number. Let the test fail in this case. */
+ signal (SIGALRM, SIG_DFL);
+ alarm (5);
+#endif
/* Test on denormalized numbers. */
for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5)
;
@@ -137,7 +144,7 @@ int main()
result |= 1;
}
/* Test on infinite numbers. */
- x = 1.0 / 0.0;
+ x = 1.0 / zero;
{
int exp;
double y = frexp (x, &exp);