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From: "isanbard at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/113514] Wrong __builtin_dynamic_object_size when
 using a set local variable
Date: Sat, 20 Jan 2024 00:47:29 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113514

--- Comment #3 from Bill Wendling <isanbard at gmail dot com> ---
(In reply to Andrew Pinski from comment #1)
> The answer is not really and it is complex.
>=20
Okay. It just seems counter-intuitive.

> So I will note that clang/LLVM returns 48 for `f.bar[argc], 1` and 0 for
> `,3`.

Yeah. I'm trying to fix that, but the consensus is that returning the maxim=
um
value of the whole object (not sub-object) when the LSB is set is okay due =
to
this in the documentation:

> If there are multiple objects ptr can point to and all of them are known =
at compile time, the returned number is the maximum of remaining byte count=
s in those objects if type & 2 is 0 and minimum if nonzero.

Note, I don't agree with that viewpoint.=