diff --git a/src/gcmain3.c b/src/gcmain3.c
index 927c1dd..bf10438 100644
--- a/src/gcmain3.c
+++ b/src/gcmain3.c
@@ -56,6 +56,10 @@ static char *id = "$Id: gcmain3.c,v 1.4 1999/05/31 23:35:31 sybalsky Exp $ Copyr
 #include "inlnPS2.h"
 #endif
 
+/* from gcscan.c */
+DLword gcscan1(register int probe);
+DLword gcscan2(register int probe);
+
 #define WORDSPERCELL 2
 #define MAXHTCNT 63
 #define PADDING 4