noeffect.c: (in macro exprNode_swap)
noeffect.c:3:59: Assignment to macro parameter: e1
  A macro parameter is used as the left side of an assignment expression. This
  exhibits behavior that could not be implemented by a function. (Use
  -macroassign to inhibit warning)
noeffect.c:3:72: Assignment to macro parameter: e2
noeffect.c:2:18: File static function exprNode_swap declared but not used
  A function is declared but not used. Use /*@unused@*/ in front of function
  header to suppress message. (Use -fcnuse to inhibit warning)
   noeffect.c:3: Definition of exprNode_swap

Finished checking --- 3 code warnings, as expected