[Bug c/117687] Wzero-as-nullpointer-constant should warn for zeros of type bool, enum, and _BitInt

[uecker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117687

--- Comment #4 from uecker at gcc dot gnu.org ---
Created attachment 63116
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=63116&action=edit
preliminary patch


Tentative patch.