--- ruby-2.0.0-p247.orig/missing/isinf.c	2011-05-15 13:55:52.000000000 +0200
+++ ruby-2.0.0-p247/missing/isinf.c	2013-10-24 09:18:55.000000000 +0200
@@ -5,6 +5,7 @@
 #define _IEEE 1
 #include <nan.h>
 
+
 int
 isinf(double n)
 {
@@ -52,6 +53,8 @@ static double zero(void) { return 0.0; }
 static double one (void) { return 1.0; }
 static double inf (void) { return one() / zero(); }
 
+#undef isinf
+
 int
 isinf(double n)
 {
