diff --git a/c/malloc_speed_test/pool_list.c b/c/malloc_speed_test/pool_list.c
index 4ff0f8d..b6034e7 100644
--- a/c/malloc_speed_test/pool_list.c
+++ b/c/malloc_speed_test/pool_list.c
@@ -73,13 +73,12 @@ inline void pool_free(void *p)
 		return;
 
 	struct block_s *b1 = (struct block_s *)(p - 2 * sizeof(struct block_s *)),
-	               *b0 = b1->prev,
 		       *b2 = b1->next;
 
-	if (b0)
-		b0->next = b2;
+	if (b1->prev)
+		b1->prev->next = b2;
 	if (b2)
-		b2->prev = b0;
+		b2->prev = b1->prev;
 
 	if (free_pool) {
 		b1->next = free_pool;