diff --git a/lib/cmdline_kunit.c b/lib/cmdline_kunit.c
index d4572dbc9145..705b82736be0 100644
--- a/lib/cmdline_kunit.c
+++ b/lib/cmdline_kunit.c
@@ -124,7 +124,7 @@ static void cmdline_do_one_range_test(struct kunit *test, const char *in,
 			    n, e[0], r[0]);
 
 	p = memchr_inv(&r[1], 0, sizeof(r) - sizeof(r[0]));
-	KUNIT_EXPECT_PTR_EQ_MSG(test, p, NULL, "in test %u at %u out of bound", n, p - r);
+	KUNIT_EXPECT_PTR_EQ_MSG(test, p, NULL, "in test %u at %td out of bound", n, p - r);
 }
 
 static void cmdline_test_range(struct kunit *test)