I think this issue should be about fixing the tests so that people
looking at the sanitizer buildbots can move on.

GH-18969 fixes "<?", ">?" and "!?", which clearly used wrong
semantics with the new compiler behavior. This should be an
uncontroversial fix that also takes care of test_struct.


Can we please discuss native _Bool in another issue?

There is no non-hackish way of unpacking _Bool if new compilers
essentially treat values outside [0, 1] as a trap representation.


You could determine sizeof(_Bool), use the matching unsigned type,
unpack as that, then cast to _Bool. But do you really want to force
that procedure on all array libraries that want to be PEP-3118
compatible?

I'd rather deprecate _Bool and use uint8_t, but that definitely
deserves a separate issue.