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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug sanitizer/108894] -fsanitize=bounds missing bounds provided by
 __builtin_dynamic_object_size()
Date: Thu, 23 Feb 2023 21:13:37 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108894

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to qinzhao from comment #9)
> (In reply to Jakub Jelinek from comment #8)
> > Well, -fsanitize=3Dbounds-strict certainly shouldn't imply
> > -fstrict-flex-arrays=3D2,
> > it should just treat [1] and [4] (but I think it does even [0] right no=
w) as
> > regular arrays for the purposes of the sanitization.
>=20
> with a small example I just tested, with -fsanitize=3Dbounds-strict, I can
> see, it treats:
>    [], [0] as flexible array members;
> but
>    [1], [4] as regular arrays
>=20
> This is the same level as -fstrict-flex-arrays=3D2.=20
> should we just keep its default behavior like this, or let it more strict=
ly
> as -fstrict-flex-arrays=3D3?

I'd keep its current behavior, perhaps except for -fsanitize=3Dbounds-strict
-fstrict-flex-arrays{,=3D3} so that -fsanitize=3Dbounds -fstrict-flex-array=
s{,=3D3}
wouldn't be more strict than the former.=