$NetBSD: patch-ac,v 1.3 2006/02/02 14:10:45 joerg Exp $

--- blitz/mathfunc.h.orig	2006-02-02 14:06:44.000000000 +0000
+++ blitz/mathfunc.h
@@ -1545,6 +1545,8 @@ public:
         // Some platforms define isnan as a macro, which causes the
         // BZ_IEEEMATHFN_SCOPE macro to break.
         return isnan(x);
+#elif defined(_GLIBCXX_USE_C99_MATH) && !defined(_GLIBCXX_USE_C99_FP_MACROS_DYNAMIC)
+	return BZ_MATHFN_SCOPE(isnan)(x);
 #else
         return BZ_IEEEMATHFN_SCOPE(isnan)(x);
 #endif