diff --git a/buf/buf0buf.c b/buf/buf0buf.c
index 7158644f791..73ffa7caad6 100644
--- a/buf/buf0buf.c
+++ b/buf/buf0buf.c
@@ -610,9 +610,9 @@ buf_block_init(
 	block->index = NULL;
 
 	block->in_free_list = FALSE;
-	block->in_LRU_list = FALSE;
 
 #ifdef UNIV_DEBUG
+	block->in_LRU_list = FALSE;
 	block->n_pointers = 0;
 #endif /* UNIV_DEBUG */
 	page_zip_des_init(&block->page.zip);
@@ -791,7 +791,7 @@ buf_chunk_free(
 		ut_a(buf_block_get_state(block) == BUF_BLOCK_NOT_USED);
 		ut_a(!block->page.zip.data);
 
-		ut_a(!block->in_LRU_list);
+		ut_ad(!block->in_LRU_list);
 		/* Remove the block from the free list. */
 		ut_a(block->in_free_list);
 		UT_LIST_REMOVE(free, buf_pool->free, block);
diff --git a/buf/buf0lru.c b/buf/buf0lru.c
index c5f110396be..3db7cdf5d28 100644
--- a/buf/buf0lru.c
+++ b/buf/buf0lru.c
@@ -208,7 +208,7 @@ buf_LRU_free_block(
 	ut_ad(mutex_own(&block->mutex));
 #endif /* UNIV_SYNC_DEBUG */
 
-	ut_a(block->in_LRU_list);
+	ut_ad(block->in_LRU_list);
 
 	if (!buf_flush_ready_for_replace(block)) {
 
@@ -444,7 +444,7 @@ loop:
 		UT_LIST_REMOVE(free, buf_pool->free, block);
 		block->in_free_list = FALSE;
 		ut_a(buf_block_get_state(block) != BUF_BLOCK_FILE_PAGE);
-		ut_a(!block->in_LRU_list);
+		ut_ad(!block->in_LRU_list);
 
 		if (buf_block_get_zip_size(block) != zip_size) {
 			page_zip_set_size(&block->page.zip, zip_size);
@@ -576,7 +576,7 @@ buf_LRU_old_adjust_len(void)
 		old_len = buf_pool->LRU_old_len;
 		new_len = 3 * (UT_LIST_GET_LEN(buf_pool->LRU) / 8);
 
-		ut_a(buf_pool->LRU_old->in_LRU_list);
+		ut_ad(buf_pool->LRU_old->in_LRU_list);
 
 		/* Update the LRU_old pointer if necessary */
 
@@ -621,7 +621,7 @@ buf_LRU_old_init(void)
 
 	while (block != NULL) {
 		ut_a(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
-		ut_a(block->in_LRU_list);
+		ut_ad(block->in_LRU_list);
 		block->old = TRUE;
 		block = UT_LIST_GET_NEXT(LRU, block);
 	}
@@ -647,7 +647,7 @@ buf_LRU_remove_block(
 #endif /* UNIV_SYNC_DEBUG */
 
 	ut_a(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
-	ut_a(block->in_LRU_list);
+	ut_ad(block->in_LRU_list);
 
 	/* If the LRU_old pointer is defined and points to just this block,
 	move it backward one step */
@@ -667,7 +667,9 @@ buf_LRU_remove_block(
 
 	/* Remove the block from the LRU list */
 	UT_LIST_REMOVE(LRU, buf_pool->LRU, block);
+#ifdef UNIV_DEBUG
 	block->in_LRU_list = FALSE;
+#endif /* UNIV_DEBUG */
 
 	/* If the LRU list is so short that LRU_old not defined, return */
 	if (UT_LIST_GET_LEN(buf_pool->LRU) < BUF_LRU_OLD_MIN_LEN) {
@@ -717,9 +719,11 @@ buf_LRU_add_block_to_end_low(
 		block->LRU_position = buf_pool_clock_tic();
 	}
 
-	ut_a(!block->in_LRU_list);
+	ut_ad(!block->in_LRU_list);
 	UT_LIST_ADD_LAST(LRU, buf_pool->LRU, block);
+#ifdef UNIV_DEBUG
 	block->in_LRU_list = TRUE;
+#endif /* UNIV_DEBUG */
 
 	if (UT_LIST_GET_LEN(buf_pool->LRU) >= BUF_LRU_OLD_MIN_LEN) {
 
@@ -764,7 +768,7 @@ buf_LRU_add_block_low(
 #endif /* UNIV_SYNC_DEBUG */
 
 	ut_a(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
-	ut_a(!block->in_LRU_list);
+	ut_ad(!block->in_LRU_list);
 
 	block->old = old;
 	cl = buf_pool_clock_tic();
@@ -786,7 +790,9 @@ buf_LRU_add_block_low(
 		block->LRU_position = (buf_pool->LRU_old)->LRU_position;
 	}
 
+#ifdef UNIV_DEBUG
 	block->in_LRU_list = TRUE;
+#endif /* UNIV_DEBUG */
 
 	if (UT_LIST_GET_LEN(buf_pool->LRU) > BUF_LRU_OLD_MIN_LEN) {
 
diff --git a/include/buf0buf.h b/include/buf0buf.h
index fd38b177192..bab96279b0e 100644
--- a/include/buf0buf.h
+++ b/include/buf0buf.h
@@ -794,8 +794,10 @@ struct buf_block_struct{
 					debugging */
 	UT_LIST_NODE_T(buf_block_t) LRU;
 					/* node of the LRU list */
+#ifdef UNIV_DEBUG
 	ibool		in_LRU_list;	/* TRUE of the page is in the LRU list;
 					used in debugging */
+#endif /* UNIV_DEBUG */
 	ulint		LRU_position;	/* value which monotonically
 					decreases (or may stay constant if
 					the block is in the old blocks) toward