diff --git a/include/stdex/compat.hpp b/include/stdex/compat.hpp
index 4717bd2f1..280406dd0 100644
--- a/include/stdex/compat.hpp
+++ b/include/stdex/compat.hpp
@@ -10,7 +10,8 @@
 #include "windows.h"
 #include <sal.h>
 #include <tchar.h>
-#else
+#endif
+#if __has_include(<uchar.h>)
 #include <uchar.h>
 #endif
 #include <locale>
diff --git a/include/stdex/string.hpp b/include/stdex/string.hpp
index f70af44c9..b490f9f31 100644
--- a/include/stdex/string.hpp
+++ b/include/stdex/string.hpp
@@ -14,7 +14,7 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <time.h>
-#ifdef _WIN32
+#if __has_include(<uchar.h>)
 #include <uchar.h>
 #endif
 #ifdef __APPLE__