Is NEGATE_EXPR gimple valid for pointer (and offset) types

[Andrew Pinski via Gcc]

While debugging PR 100925, I found that after my match.pd (for
A?CST0:CST1) and phiopt patch to use match-and-simplify, gcc will
produce an negate assignment gimple which has a pointer type (and
offset type).  Before we would produce "cond ? -1B : 0B" in this case
but now we produce:
  _4 = a_2(D) == 0;
  _5 = (void *) _4;
  _6 = -_5;
Which I think would be invalid gimple but the verifiers don't say it is.
Should the verifier reject this gimple and similar ones?  I am going
to do some simple testing to see what code hits it too.

Thanks,
Andrew Pinski