diff --git a/lib/dns/name.c b/lib/dns/name.c
index 2c021aad1f..e751194478 100644
--- a/lib/dns/name.c
+++ b/lib/dns/name.c
@@ -1345,7 +1345,7 @@ dns_name_totext2(const dns_name_t *name, unsigned int options,
 	unsigned int trem, count;
 	unsigned int labels;
 	bool saw_root = false;
-	unsigned int oused = target->used;
+	unsigned int oused;
 	dns_name_totextfilter_t *mem;
 	dns_name_totextfilter_t totext_filter_proc = NULL;
 	isc_result_t result;
@@ -1358,6 +1358,8 @@ dns_name_totext2(const dns_name_t *name, unsigned int options,
 	REQUIRE(VALID_NAME(name));
 	REQUIRE(ISC_BUFFER_VALID(target));
 
+	oused = target->used;
+
 	result = totext_filter_proc_key_init();
 	if (result != ISC_R_SUCCESS)
 		return (result);