fix test-poll compilation failure on Cygwin

[gnulib.git] / lib / isnanf.h

diff --git a/lib/isnanf.h b/lib/isnanf.h
index a3ae92f..69492e1 100644 (file)
--- a/lib/isnanf.h
+++ b/lib/isnanf.h
@@ -1,24 +1,27 @@
-/* Test for NaN that does not need libm.
-   Copyright (C) 2007 Free Software Foundation, Inc.
+/* Test for NaN.
+   Copyright (C) 2007-2008 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
-   You should have received a copy of the GNU General Public License along
-   with this program; if not, write to the Free Software Foundation,
-   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
-#if HAVE_ISNANF_IN_LIBC
+#if HAVE_ISNANF
 /* Get declaration of isnan macro or (older) isnanf function.  */
 # include <math.h>
-# ifdef isnan
+# if __GNUC__ >= 4
+   /* GCC 4.0 and newer provides three built-ins for isnan.  */
+#  undef isnanf
+#  define isnanf(x) __builtin_isnanf ((float)(x))
+# elif defined isnan
 #  undef isnanf
 #  define isnanf(x) isnan ((float)(x))
 # endif