QUESTCOMPARE2

Message        <Context> the unsigned expression "<expr>" is being
               tested to see if it is greater than zero.  This might
               not be what you intended.

Description    An ordered comparison between an unsigned value and a
               constant that is zero may indicate a programming
               error.  Often C programmers do not realize that an
               expression has an unsigned type.  If the code is
               correct, the comparison could be more clearly coded
               by testing for equality with zero.

User Action    Cast (or otherwise rewrite) one of the operands of
               the compare to match the signedness of the other
               operand, or compare for equality with zero.