Remove unused variables.

[gnulib.git] / lib / isnanf.h

diff --git a/lib/isnanf.h b/lib/isnanf.h
index 67bbfc6..774942c 100644 (file)
--- a/lib/isnanf.h
+++ b/lib/isnanf.h
@@ -1,5 +1,5 @@
 /* Test for NaN that does not need libm.
-   Copyright (C) 2007 Free Software Foundation, Inc.
+   Copyright (C) 2007-2008 Free Software Foundation, Inc.
 
    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
@@ -17,7 +17,11 @@
 #if HAVE_ISNANF_IN_LIBC
 /* 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