diff --git a/sourcemm/oslink.h b/sourcemm/oslink.h
index 77e4b75..7c317ed 100644
--- a/sourcemm/oslink.h
+++ b/sourcemm/oslink.h
@@ -56,7 +56,7 @@
 #endif
 
 #if defined __linux__
-	extern int errno;
+	#include <errno.h>
 	int GetLastError();
 #endif