diff --git a/lib/EAPBase/include/EAP.h b/lib/EAPBase/include/EAP.h
index 9b63f92..c76936c 100644
--- a/lib/EAPBase/include/EAP.h
+++ b/lib/EAPBase/include/EAP.h
@@ -107,7 +107,7 @@ namespace eap
     /// \addtogroup EAPBaseDiameter
     /// @{
 
-    enum diameter_avp_flags_t;
+    enum diameter_avp_flags_t : unsigned char;
     struct diameter_avp_header;
     struct diameter_avp_header_ven;
 
diff --git a/lib/MSCHAPv2/include/MSCHAPv2.h b/lib/MSCHAPv2/include/MSCHAPv2.h
index 44b8625..7e096aa 100644
--- a/lib/MSCHAPv2/include/MSCHAPv2.h
+++ b/lib/MSCHAPv2/include/MSCHAPv2.h
@@ -23,7 +23,7 @@
 
 namespace eap
 {
-    enum chap_packet_code_t;
+    enum chap_packet_code_t : unsigned char;
     struct WINSTD_NOVTABLE chap_header;
     struct WINSTD_NOVTABLE challenge_mschapv2;
     struct WINSTD_NOVTABLE challenge_hash;
diff --git a/lib/WinStd b/lib/WinStd
index 542d20f..e776e5a 160000
--- a/lib/WinStd
+++ b/lib/WinStd
@@ -1 +1 @@
-Subproject commit 542d20fccb8233ac99b1ba60268261f2084f2e29
+Subproject commit e776e5a4737ecd725292c7581c8a9f5e26d6516a