diff --git a/include/WinStd/EAP.h b/include/WinStd/EAP.h
index fa3465dd..00f4b499 100644
--- a/include/WinStd/EAP.h
+++ b/include/WinStd/EAP.h
@@ -33,7 +33,7 @@
 
 namespace winstd
 {
-    enum eap_type_t;
+    enum eap_type_t : unsigned char;
     struct WINSTD_API EapHostPeerFreeMemory_delete;
     struct WINSTD_API EapHostPeerFreeRuntimeMemory_delete;
     struct WINSTD_API EapHostPeerFreeErrorMemory_delete;