Tests: fix possible null pointer dereference

Reported by Coverity Scan
*** CID 1297896:  Null pointer dereferences  (NULL_RETURNS)
/tests/lib/test_ctf_writer.c: 865 in append_complex_event()

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/tests/lib/test_ctf_writer.c b/tests/lib/test_ctf_writer.c
index d1a61eaa1aed70e51d07b7a4d7c484ba175f380b..60a51132f209a5727ae164cc7281b6ce427de48a 100644 (file)
--- a/tests/lib/test_ctf_writer.c
+++ b/tests/lib/test_ctf_writer.c
@@ -862,7 +862,7 @@ void append_complex_event(struct bt_ctf_stream_class *stream_class,
        ok(bt_ctf_field_type_variant_get_tag_name(NULL) == NULL,
                "bt_ctf_field_type_variant_get_tag_name handles NULL correctly");
        ret_string = bt_ctf_field_type_variant_get_tag_name(variant_type);
-       ok(!strcmp(ret_string, "variant_selector"),
+       ok(ret_string ? !strcmp(ret_string, "variant_selector") : 0,
                "bt_ctf_field_type_variant_get_tag_name returns the correct variant tag name");
        ok(bt_ctf_field_type_variant_get_field_type_by_name(NULL,
                "INT16_TYPE") == NULL,