Compiler Warning (level 4) C4214


For the latest documentation on Visual Studio 2017 RC, see Visual Studio 2017 RC Documentation.

nonstandard extension used : bit field types other than int

With the default Microsoft extensions (/Ze), bitfield structure members can be of any integer type.

// C4214.c  
// compile with: /W4  
struct bitfields  
   unsigned short j:4;  // C4214  
int main()  

Such bit fields are invalid under ANSI compatibility (/Za).