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From: "npfhrotynz-ptnqh.myvf at noclue dot notk.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/106920] -Warray-bound false positive regression with -O2 or -Os and constant address
Date: Wed, 14 Sep 2022 07:37:32 +0000	[thread overview]
Message-ID: <bug-106920-4-AWxnNiM1EK@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-106920-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106920

--- Comment #5 from Dominique Martinet <npfhrotynz-ptnqh.myvf at noclue dot notk.org> ---
hmm this is a pretty complex topic.

My problem like pointed out in
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578 is more with all the legacy
code that I have to deal with, that isn't maintained by anyone, and well the
sorry state of embedded systems upstreams in general... So I'm really just
sitting there trying to get old code to keep working with my newer gcc version.

(I actually wonder why that didn't fail with gcc11, I've been using that for a
while...)

The solution in that other bug ^ to just not issue warnings for constant
addresses is good in general and I was just unlucky that such an address
happened below 4k for this code.
I don't understand why the ast tree cannot make the difference between a
constant address and a constant null pointer macroed to hell, but since that
only happens with optimizations enabled I guess some info is lost at that point
and there was nothing to do or it would have been done.

Anyway, I consider that closed, there's been enough ink spilled in the other
thread and thank you all for the quick replies!

      parent reply	other threads:[~2022-09-14  7:37 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-13  6:44 [Bug c/106920] New: -Warray-bound false positive regression with -O2 or -Os npfhrotynz-ptnqh.myvf at noclue dot notk.org
2022-09-13  6:51 ` [Bug c/106920] " rguenth at gcc dot gnu.org
2022-09-13  7:13 ` [Bug c/106920] -Warray-bound false positive regression with -O2 or -Os and constant address npfhrotynz-ptnqh.myvf at noclue dot notk.org
2022-09-13 16:48 ` pinskia at gcc dot gnu.org
2022-09-14  7:15 ` rguenth at gcc dot gnu.org
2022-09-14  7:37 ` npfhrotynz-ptnqh.myvf at noclue dot notk.org [this message]

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