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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: Tue, 13 Sep 2022 07:13:46 +0000	[thread overview]
Message-ID: <bug-106920-4-k4GIRPK2qr@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 #2 from Dominique Martinet <npfhrotynz-ptnqh.myvf at noclue dot notk.org> ---
Thanks for the very fast reply!

since you mentioned null pointers I now see this warning doesn't happen if I
try with a larger constant, I just had bad luck that imx-atf uses an address <
4k...?


I checked the first dozen of issues from the meta-bug (from start of open bugs
list to 86613 included), but there are just too many and didn't see a
workaround in the ones I did open.

I can see catching bad casts to be useful, but for low level hardware code
accessing register addresses directly is the norm -- I'm not too worried now
I've noticed the <4k "rule" but there really can't be any assumption made with
hardware, as seen here...
(And NXP isn't exactly great at working with external entities, I tried
reaching out for another compile fix with little success... but that's
offtopic.)

Well, good to understand the reason behind that warning at least.

  parent reply	other threads:[~2022-09-13  7:13 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 ` npfhrotynz-ptnqh.myvf at noclue dot notk.org [this message]
2022-09-13 16:48 ` [Bug c/106920] -Warray-bound false positive regression with -O2 or -Os and constant address 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

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