[Bug c++/126868] -ftrivial-auto-var-init=uninitialized should be incompatible with -std=c++26 (or at least warn about it)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126868

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Giuseppe D'Angelo from comment #5)
> My code didn't have [[indeterminate]]?

It did, because you've used a flag to tell the compiler it is implied.

> But why doesn't the flag just stop the wiping, *without* re-engaging the UB,
> so the missiles still don't get fired? This way the blast radius would be
> much much smaller? (Yes, technically speaking it'd still be non-conforming
> because it doesn't wipe.)

That is not really possible in an optimizing compiler (unless you turn off all
optimizations).