diff --git a/src/flags.hh b/src/flags.hh
index a3cbc5e0..10e05187 100644
--- a/src/flags.hh
+++ b/src/flags.hh
@@ -10,7 +10,7 @@ template<typename Flags>
 struct WithBitOps : std::false_type {};
 
 template<typename Flags>
-using EnumStorageType = typename std::underlying_type<Flags>::type;
+using UnderlyingType = typename std::underlying_type<Flags>::type;
 
 template<typename Flags>
 using EnableIfWithBitOps = typename std::enable_if<WithBitOps<Flags>::value>::type;
@@ -18,33 +18,33 @@ using EnableIfWithBitOps = typename std::enable_if<WithBitOps<Flags>::value>::ty
 template<typename Flags, typename = EnableIfWithBitOps<Flags>>
 constexpr Flags operator|(Flags lhs, Flags rhs)
 {
-    return (Flags)((EnumStorageType<Flags>) lhs | (EnumStorageType<Flags>) rhs);
+    return (Flags)((UnderlyingType<Flags>) lhs | (UnderlyingType<Flags>) rhs);
 }
 
 template<typename Flags, typename = EnableIfWithBitOps<Flags>>
 Flags& operator|=(Flags& lhs, Flags rhs)
 {
-    (EnumStorageType<Flags>&) lhs |= (EnumStorageType<Flags>) rhs;
+    (UnderlyingType<Flags>&) lhs |= (UnderlyingType<Flags>) rhs;
     return lhs;
 }
 
 template<typename Flags, typename = EnableIfWithBitOps<Flags>>
 constexpr bool operator&(Flags lhs, Flags rhs)
 {
-    return ((EnumStorageType<Flags>) lhs & (EnumStorageType<Flags>) rhs) != 0;
+    return ((UnderlyingType<Flags>) lhs & (UnderlyingType<Flags>) rhs) == (UnderlyingType<Flags>)rhs;
 }
 
 template<typename Flags, typename = EnableIfWithBitOps<Flags>>
 Flags& operator&=(Flags& lhs, Flags rhs)
 {
-    (EnumStorageType<Flags>&) lhs &= (EnumStorageType<Flags>) rhs;
+    (UnderlyingType<Flags>&) lhs &= (UnderlyingType<Flags>) rhs;
     return lhs;
 }
 
 template<typename Flags, typename = EnableIfWithBitOps<Flags>>
 constexpr Flags operator~(Flags lhs)
 {
-    return (Flags)(~(EnumStorageType<Flags>)lhs);
+    return (Flags)(~(UnderlyingType<Flags>)lhs);
 }
 
 }