bug#47080: 28.0.50; Spurious variable left uninitialized compiler warning

[Stefan Monnier]

>> Indeed, the warning could even be generalized to other trivial constant
>> values like `t`, but I think what we have already gives enough false
>> positives ;-)
> FWIW, I also got one or two true positives in my own stuff.
> To avoid false positives, is it possible to limit the warning to "human
> written" code or to code that is not the result of macro expansion?

It's somewhere between difficult and impossible with the current setup.
Hygienic macro systems should be able to get that information, but
our macro system doesn't keep track of it.

It would require efforts similar to those needed to preserve
file+line+col information.


        Stefan