diff --git a/test/src/unit-msgpack.cpp b/test/src/unit-msgpack.cpp
index 1c4c8edc2..123eb9e15 100644
--- a/test/src/unit-msgpack.cpp
+++ b/test/src/unit-msgpack.cpp
@@ -349,7 +349,7 @@ TEST_CASE("MessagePack")
                 {
                     for (uint64_t i :
                             {
-                                4294967296lu, 9223372036854775807lu
+                                4294967296LU, 9223372036854775807LU
                             })
                     {
                         CAPTURE(i)