diff --git a/lib/isc/hash.c b/lib/isc/hash.c
index e12c47183f..b69ca3f665 100644
--- a/lib/isc/hash.c
+++ b/lib/isc/hash.c
@@ -302,7 +302,6 @@ static void
 destroy(isc_hash_t **hctxp) {
 	isc_hash_t *hctx;
 	isc_mem_t *mctx;
-	unsigned char canary0[4], canary1[4];
 
 	REQUIRE(hctxp != NULL && *hctxp != NULL);
 	hctx = *hctxp;
@@ -324,10 +323,7 @@ destroy(isc_hash_t **hctxp) {
 
 	DESTROYLOCK(&hctx->lock);
 
-	memmove(canary0, hctx + 1, sizeof(canary0));
 	memset(hctx, 0, sizeof(isc_hash_t));
-	memmove(canary1, hctx + 1, sizeof(canary1));
-	INSIST(memcmp(canary0, canary1, sizeof(canary0)) == 0);
 	isc_mem_put(mctx, hctx, sizeof(isc_hash_t));
 	isc_mem_detach(&mctx);
 }