4523			An expression of 'essentially enum' type (%1s) is being used as the left-hand operand of this shift operator (%2s).
	Arithmetic type - Operands

/*PRQA S 1-9999 ++*/
/*PRQA S 4523 --*/

enum E {ONE, TWO};

void f4523 (enum E a)
{
  TWO << 1;                 /* 4523 */
  
  a >> 1;                   /* 4523 */
}

MISRA C:2012 Rules applicable to message 4523:

See also:

• 4522 An expression of 'essentially enum' type (%1s) is being used as the %2s operand of this bitwise operator (%3s).
• 4524 An expression of 'essentially enum' type (%1s) is being used as the right-hand operand of this shift operator (%2s).