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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	[thread overview]
Message-ID: <bug-113514-4-96lYHvOwlV@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113514-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113514

--- 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.
> 
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 maximum
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 counts in those objects if type & 2 is 0 and minimum if nonzero.

Note, I don't agree with that viewpoint.

  parent reply	other threads:[~2024-01-20  0:47 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-19 23:59 [Bug c/113514] New: " isanbard at gmail dot com
2024-01-20  0:12 ` [Bug middle-end/113514] " pinskia at gcc dot gnu.org
2024-01-20  0:18 ` pinskia at gcc dot gnu.org
2024-01-20  0:47 ` isanbard at gmail dot com [this message]
2024-01-20  1:15 ` sjames at gcc dot gnu.org
2024-01-22 13:58 ` siddhesh at gcc dot gnu.org
2024-01-22 13:59 ` [Bug middle-end/113514] Imprecise " siddhesh at gcc dot gnu.org

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