[Bug middle-end/101134] Bogus -Wstringop-overflow warning about non-existent overflow

["dangelog at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101134

--- Comment #8 from Giuseppe D'Angelo <dangelog at gmail dot com> ---
In a -Wall build, it's a bit unfair to pretend the users to know if a warning
is being generated by the frontend, the middleend, the backend and so on. All
they get is a list of warnings saying "this is like this, this is like that".
You're saying that all such warnings should be treated as "maybe", as false
positives are a possibility. But I don't agree with this. 

First, as I said, the mood of the warning is "indicative", which denotes
certainty and reality, not possibility. (But I'll grant, not being a native
English speaker, this may just be a personal impression of the warning being
"stern".)

Second, the presence of things like -Wmaybe-uninitialized vs -Wuninitialized
hints at the fact that GCC *wants* to distinguish these "maybe" vs. "certain"
cases, at least in certain contexts (like, where it CAN do that!), and give
different warnings if it can.

Third, frontend warnings simply don't have false positives: if the compiler
tells you "this function may be marked override", "this class has virtual
functions but no virtual destructor", "this case label falls through into the
next one", that's absolutely true in 100% of the cases. A false positive here
would clearly be treated as a bug in GCC, and not dismissed as "but it's a
warning, and a warning is just a 'maybe', and yes, GCC is telling you to add
`override`, and then you added it, and now the program doesn't even build any
more because the warning was wrong and `override` was not even needed, but see,
it's your fault for not understanding the 'maybe' part".

So, in a nutshell, yes, I'd be much more comfortable if warnings that denote a
possibility (for any reason, really, I'm not asking to NEVER generate false
positives) would simply have "may" or "might" added to their text. If that's
the majority of middle-end warnings because they all generate false positives,
why would that be a problem, in principle?

But fair enough, let's agree to disagree. :)