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From: "ch3root at openwall dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/94103] Wrong optimization: reading value of a variable changes its representation for optimizer
Date: Fri, 20 Mar 2020 12:32:28 +0000	[thread overview]
Message-ID: <bug-94103-4-OdU7jfjGmj@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-94103-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94103

--- Comment #10 from Alexander Cherepanov <ch3root at openwall dot com> ---
The case of assignment+memcpy -- testcases in comment 0, in pr92824 and similar
-- is fixed.

But the case of memset+assignment -- pr93270 and pr61872 (these seem to be
dups) -- is not fixed. Is it supposed to be fixed?

Before, I've seen somewhat contradicting approaches in bug 92486, comment 12,
which says that memset+assignment should set padding in structs, and in bug
93270, comment 4, which implies that memset+assignment shouldn't set padding in
long double. I'm in no way trying to imply that memset+assignment should or
shouldn't be fixed, just wondering if there is a difference of two cases.

  parent reply	other threads:[~2020-03-20 12:32 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-09 17:45 [Bug middle-end/94103] New: " ch3root at openwall dot com
2020-03-09 17:46 ` [Bug middle-end/94103] " ch3root at openwall dot com
2020-03-09 17:50 ` pinskia at gcc dot gnu.org
2020-03-09 22:30 ` ch3root at openwall dot com
2020-03-10  9:39 ` [Bug target/94103] " rguenth at gcc dot gnu.org
2020-03-10 13:41 ` ch3root at openwall dot com
2020-03-12  4:13 ` law at redhat dot com
2020-03-12 13:21 ` rguenth at gcc dot gnu.org
2020-03-12 13:23 ` rguenth at gcc dot gnu.org
2020-03-12 13:36 ` marxin at gcc dot gnu.org
2020-03-20 12:32 ` ch3root at openwall dot com [this message]
2020-03-20 14:25 ` rguenther at suse dot de
2020-03-20 14:44 ` schwab@linux-m68k.org
2020-03-20 16:29 ` ch3root at openwall dot com
2020-03-20 16:41 ` rguenther at suse dot de
2020-03-20 17:47 ` ch3root at openwall dot com
2020-03-20 17:53 ` rguenther at suse dot de
2020-04-02 14:49 ` cvs-commit at gcc dot gnu.org
2020-04-15  9:58 ` rguenth at gcc dot gnu.org

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