[Bug c/103502] -Wstrict-aliasing=3 doesn't warn on what is documented as UB

["stsp at users dot sourceforge.net" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103502

--- Comment #7 from Stas Sergeev <stsp at users dot sourceforge.net> ---
(In reply to Eric Gallager from comment #6)
> -Wstrict-aliasing is kind of confusing in this regards since it's different
> from how other warnings with numerical levels work. Normally a higher
> numerical value to a warning option means "print more warnings" but for
> -Wstrict-aliasing it means "try harder to reduce the number of warnings".

Number of warnings, or number
of false-positives?
This is what is still unclear
to me. If it reduces the number
of warnings (including valid ones,
by not applying some checks for
example), then indeed what you propose
can be done (or not done - it would
be rather straight-forward anyway).

But I had the following assumptions:
1. It reduces the number of only false-positives
2. It increases the amount of warnings by avoiding false-negatives
(i.e. by not "hiding" the warnings that lower
levels could miss)
3. The warning I've seen on lower levels was a valid one

I suppose what you propose, can
be done if 2 is not true.
I still don't know which of the
above wasn't true.