diff --git a/Tests/LibJS/test262-runner.cpp b/Tests/LibJS/test262-runner.cpp
index 302fbc6155..4f96cdad48 100644
--- a/Tests/LibJS/test262-runner.cpp
+++ b/Tests/LibJS/test262-runner.cpp
@@ -560,7 +560,7 @@ void __assertion_failed(char const* assertion)
     handle_failed_assert(assertion);
 }
 #else
-#    if AK_OS_EMSCRIPTEN
+#    ifdef AK_OS_EMSCRIPTEN
 extern "C" __attribute__((__noreturn__)) void __assert_fail(char const* assertion, char const* file, int line, char const* function)
 #    else
 extern "C" __attribute__((__noreturn__)) void __assert_fail(char const* assertion, char const* file, unsigned int line, char const* function)