diff --git a/lib/dns/rbt.c b/lib/dns/rbt.c
index 4cfc1769af..f845725f47 100644
--- a/lib/dns/rbt.c
+++ b/lib/dns/rbt.c
@@ -775,17 +775,18 @@ treefix(dns_rbt_t *rbt, void *base, size_t filesize, dns_rbtnode_t *n,
 	uint64_t *crc) {
 	isc_result_t result = ISC_R_SUCCESS;
 	dns_fixedname_t fixed;
-	dns_name_t nodename, *fullname;
-	unsigned char *node_data;
+	dns_name_t nodename, *fullname = NULL;
+	unsigned char *node_data = NULL;
 	dns_rbtnode_t header;
-	size_t datasize, nodemax = filesize - sizeof(dns_rbtnode_t);
+	size_t nodemax = filesize - sizeof(dns_rbtnode_t);
+	size_t datasize;
 
 	if (n == NULL) {
 		return (ISC_R_SUCCESS);
 	}
 
 	CONFIRM((void *)n >= base);
-	CONFIRM((char *)n - (char *)base <= (int)nodemax);
+	CONFIRM((size_t)((char *)n - (char *)base) <= nodemax);
 	CONFIRM(DNS_RBTNODE_VALID(n));
 
 	dns_name_init(&nodename, NULL);
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index 3b5035ea34..a5068d0f3a 100644
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -7579,7 +7579,7 @@ rbt_datafixer(dns_rbtnode_t *rbtnode, void *base, size_t filesize, void *arg,
  * Load the RBT database from the image in 'f'
  */
 static isc_result_t
-deserialize32(void *arg, FILE *f, off_t offset) {
+deserialize(void *arg, FILE *f, off_t offset) {
 	isc_result_t result;
 	rbtdb_load_t *loadctx = arg;
 	dns_rbtdb_t *rbtdb = loadctx->rbtdb;
@@ -7724,7 +7724,7 @@ beginload(dns_db_t *db, dns_rdatacallbacks_t *callbacks) {
 
 	callbacks->add = loading_addrdataset;
 	callbacks->add_private = loadctx;
-	callbacks->deserialize = deserialize32;
+	callbacks->deserialize = deserialize;
 	callbacks->deserialize_private = loadctx;
 
 	return (ISC_R_SUCCESS);