Fixed the PACK() macro.
diff --git a/src/base/ftgrays.c b/src/base/ftgrays.c
index e006a35..f6cad89 100644
--- a/src/base/ftgrays.c
+++ b/src/base/ftgrays.c
@@ -947,8 +947,8 @@
/* a macro comparing two cell pointers. Returns true if a <= b. */
#if 1
-#define PACK( a ) ( ( (long)(a)->y << 16 ) | (a)->x )
-#define LESS_THAN( a, b ) ( PACK(a) < PACK(b) )
+#define PACK( a ) ( ( (long)(a)->y << 16 ) + (a)->x )
+#define LESS_THAN( a, b ) ( PACK( a ) < PACK( b ) )
#else /* 1 */
#define LESS_THAN( a, b ) ( (a)->y < (b)->y || \
( (a)->y == (b)->y && (a)->x < (b)->x ) )