diff --git a/src/test/SDL_test_harness.c b/src/test/SDL_test_harness.c
index 74e898efc..7f4c39e38 100644
--- a/src/test/SDL_test_harness.c
+++ b/src/test/SDL_test_harness.c
@@ -564,7 +564,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
                             execKey = SDLTest_GenerateExecKey((char *)runSeed, testSuite->name, testCase->name, iterationCounter);
                         }
 
-                        SDLTest_Log("Test Iteration %i: execKey %" PRIu64 "", iterationCounter, execKey);
+                        SDLTest_Log("Test Iteration %i: execKey %llu", iterationCounter, (long long unsigned)execKey);
                         testResult = SDLTest_RunTest(testSuite, testCase, execKey);
 
                         if (testResult == TEST_RESULT_PASSED) {