diff --git a/src/backend/utils/mmgr/slab.c b/src/backend/utils/mmgr/slab.c
index 11a126a..463177f 100644
--- a/src/backend/utils/mmgr/slab.c
+++ b/src/backend/utils/mmgr/slab.c
@@ -570,6 +570,7 @@ SlabRealloc(MemoryContext context, void *pointer, Size size)
 		return pointer;
 
 	elog(ERROR, "slab allocator does not support realloc()");
+	return NULL;		/* keep compiler quiet */
 }
 
 /*