diff --git a/include/rm.h b/include/rm.h
index 14005d90a..060a1c22f 100644
--- a/include/rm.h
+++ b/include/rm.h
@@ -104,6 +104,8 @@ enum levl_typ_types {
 #define IS_WALL(typ) ((typ) && (typ) <= DBWALL)
 #define IS_STWALL(typ) ((typ) <= DBWALL) /* STONE <= (typ) <= DBWALL */
 #define IS_OBSTRUCTED(typ) ((typ) < POOL)      /* absolutely nonaccessible */
+#define IS_CORR(typ) ((typ) == CORR || (typ) == SCORR)
+#define IS_SDOOR(typ) ((typ) == SDOOR)
 #define IS_DOOR(typ) ((typ) == DOOR)
 #define IS_DOORJOIN(typ) (IS_OBSTRUCTED(typ) || (typ) == IRONBARS)
 #define IS_TREE(typ)                                            \
diff --git a/src/display.c b/src/display.c
index 30eb249dd..c379331e5 100644
--- a/src/display.c
+++ b/src/display.c
@@ -3101,7 +3101,7 @@ check_pos(coordxy x, coordxy y, int which)
     if (!isok(x, y))
         return which;
     type = levl[x][y].typ;
-    if (IS_OBSTRUCTED(type) || type == CORR || type == SCORR)
+    if (IS_STWALL(type) || IS_CORR(type) || IS_SDOOR(type))
         return which;
     return 0;
 }