MISRA.BITFIELD.TYPE.CPP

Type of bit-field is neither bool, nor signed/unsigned integer.

MISRA-C++ Rule 9-6-2 (required): Bit-fields shall be either bool type or an explicitly unsigned or signed integral type.

[Implementation 3.9.1(5), 7.1.5.2(1), 9.6(3)]

Rationale

Using int is implementation-defined because bit-fields of type int can be either signed or unsigned. The use of wchar_t as a bit-field type is prohibited as ISO/IEC 14882:2003 [1] does not explicitly define the underlying representation as signed or unsigned.

Example

struct S
{
     signed int   a : 2;   // Compliant
   unsigned int   b : 2;   // Compliant
            char  c : 2;   // Non-compliant
     signed char  d : 2;   // Compliant
   unsigned char  e : 2;   // Compliant
            short f : 2;   // Non-compliant
     signed short g : 2;   // Compliant
   unsigned short h : 2;   // Compliant
            int   i : 2;   // Non-compliant
            bool  j : 2;   // Compliant
         wchar_t  k : 2;   // Non-compliant
        uint32_t  l : 2;   // Compliant
          int8_t  m : 2;   // Compliant
};