diff --git a/bin/tests/adb_test.c b/bin/tests/adb_test.c
index 6bb73077e8..c7691c591c 100644
--- a/bin/tests/adb_test.c
+++ b/bin/tests/adb_test.c
@@ -245,7 +245,7 @@ lookup(const char *target) {
 	INSIST(target != NULL);
 
 	client = new_client();
-	isc_buffer_init(&t, target, strlen(target));
+	isc_buffer_constinit(&t, target, strlen(target));
 	isc_buffer_add(&t, strlen(target));
 	isc_buffer_init(&namebuf, namedata, sizeof(namedata));
 	dns_name_init(&name, NULL);
diff --git a/bin/tests/db_test.c b/bin/tests/db_test.c
index 3ce4ea7700..b367eeba84 100644
--- a/bin/tests/db_test.c
+++ b/bin/tests/db_test.c
@@ -263,7 +263,7 @@ load(const char *filename, const char *origintext, isc_boolean_t cache) {
 	ISC_LINK_INIT(dbi, link);
 
 	len = strlen(origintext);
-	isc_buffer_init(&source, origintext, len);
+	isc_buffer_constinit(&source, origintext, len);
 	isc_buffer_add(&source, len);
 	dns_fixedname_init(&forigin);
 	origin = dns_fixedname_name(&forigin);
diff --git a/bin/tests/sig0_test.c b/bin/tests/sig0_test.c
index f0292c90b5..037216588f 100644
--- a/bin/tests/sig0_test.c
+++ b/bin/tests/sig0_test.c
@@ -262,7 +262,7 @@ main(int argc, char *argv[]) {
 
 	dns_fixedname_init(&fname);
 	name = dns_fixedname_name(&fname);
-	isc_buffer_init(&b, "child.example.", strlen("child.example."));
+	isc_buffer_constinit(&b, "child.example.", strlen("child.example."));
 	isc_buffer_add(&b, strlen("child.example."));
 	result = dns_name_fromtext(name, &b, dns_rootname, ISC_FALSE, NULL);
 	CHECK("dns_name_fromtext", result);
diff --git a/bin/tests/zone_test.c b/bin/tests/zone_test.c
index 85ed9c83ce..b00c7c9e5c 100644
--- a/bin/tests/zone_test.c
+++ b/bin/tests/zone_test.c
@@ -100,7 +100,7 @@ setup(const char *zonename, const char *filename, const char *classname) {
 
 	dns_zone_settype(zone, zonetype);
 
-	isc_buffer_init(&buffer, zonename, strlen(zonename));
+	isc_buffer_constinit(&buffer, zonename, strlen(zonename));
 	isc_buffer_add(&buffer, strlen(zonename));
 	dns_fixedname_init(&fixorigin);
 	result = dns_name_fromtext(dns_fixedname_name(&fixorigin),