Imported Upstream version 1.4.17

[platform/upstream/m4.git] / m4 / frexp.m4

diff --git a/m4/frexp.m4 b/m4/frexp.m4
index 2e0fb3b..2eb98a1 100644 (file)
--- 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.
 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.])
   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])
 ])
   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.])
   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
 ])
 
   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 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_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(
   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>
 #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
 /* 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)
 #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;
   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)
     ;
   /* 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.  */
         result |= 1;
     }
   /* Test on infinite numbers.  */

-  x = 1.0 / 0.0;
+  x = 1.0 / zero;

   {
     int exp;
     double y = frexp (x, &exp);
   {
     int exp;
     double y = frexp (x, &exp);