Fix compile errors in Clang

src/common/swap.h

@@ -85,7 +85,6 @@ public:
         return *this;
     }
 
-    operator long() const { return (long)swap(); }    
     operator s8() const { return (s8)swap(); }
     operator u8() const { return (u8)swap(); }
     operator s16() const { return (s16)swap(); }