Index: /issm/trunk-jpl/src/c/shared/Numerics/isnan.h
===================================================================
--- /issm/trunk-jpl/src/c/shared/Numerics/isnan.h	(revision 12544)
+++ /issm/trunk-jpl/src/c/shared/Numerics/isnan.h	(revision 12545)
@@ -6,11 +6,9 @@
 #define _XISNAN_H_
 
-#ifdef _INTEL_WIN_
-int isnan(IssmPDouble X);
-#endif
+#include <cmath>
 
 template <class T> int xIsNan(const T& X) {
 #ifdef _INTEL_WIN_
-		return (x!=x)?1:0;
+		return (X!=X)?1:0;
 #else
 		return isnan(X);