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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/103483] context-sensitive ranges change triggers
 stringop-overread
Date: Wed, 01 Dec 2021 23:44:12 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103483

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #8)
> I think we should come up with a better plan in general for "flow sensati=
ve"
> warnings really. Maybe only enable them with -O2 and above. But we keep on
> getting more and more of them where it is only defined at runtime if it is
> hit.
> The other thing is not having it in -W -Wall. Or maybe even adding a way
> (outside of -fsantizer=3D*) to have runtime checks inside the flow where =
this
> happen.

Just to note, I was wrong before in talking about this case (and others)
because I didn't realize how much code is going to run into these issues. I
think Aldy did put it correct when he wrote: "These false positives "by des=
ign"
arguments are just a cop-out.".=