diff --git a/src/misc.c b/src/misc.c
index 123656cba..7f8ea407c 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -386,6 +386,7 @@ char * clipboard_pull_text()
 
 int register_extension()
 {
+#if defined INSTALLABLE
 #if defined WIN32
 	
 	LONG rresult;
@@ -455,6 +456,9 @@ int register_extension()
 #elif defined MACOSX
 	return 0;
 #endif
+#else
+	return 0;
+#endif
 }
 
 vector2d v2d_zero = {0,0};