diff --git a/src/detect.c b/src/detect.c
index 2b1e16fff..c5acc0cb3 100644
--- a/src/detect.c
+++ b/src/detect.c
@@ -712,7 +712,6 @@ register struct obj *sobj;
 /* sobj is null if crystal ball, *scroll if gold detection scroll */
 {
     register struct trap *ttmp;
-    register struct obj *obj;
     struct monst *mon;
     int door, glyph, tr;
     int uw = u.uinwater, cursed_src = sobj && sobj->cursed;