diff --git bionetgen-BioNetGen-2.2.6-stable/bng2/Network3/src/network.h~ bionetgen-BioNetGen-2.2.6-stable/bng2/Network3/src/network.h
index 0191fca85c..5292d9fa7d 100644
--- bionetgen-BioNetGen-2.2.6-stable/bng2/Network3/src/network.h~
+++ bionetgen-BioNetGen-2.2.6-stable/bng2/Network3/src/network.h
@@ -39,8 +39,6 @@ using namespace std;
 
 #include <cmath>
 
-extern "C" int isnan(double);
-
 // Reaction types
 enum {ELEMENTARY, SATURATION, MICHAELIS_MENTEN, HILL, FUNCTIONAL};