From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 5AD073858C50; Thu, 11 Apr 2024 19:18:57 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5AD073858C50
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1712863137;
	bh=9OjvwfgxcsPw17/iWZ/7xQVVwM7yTttLxqScl5+Pk00=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=ZkW5Y1bXHPR1/8hUrB+WPIg5iQ9dbacB4ryCYe8PbTfcNhi7dCSvFGvOWUPtxkJD6
	 DOUAQl8s+fgqS/28CYRT3O/Tk7gosBwwkXm9Y3pVVABeGS6PTqYbmO2mD3tzXPZLPb
	 ogspyYfhaJl9CnVoDLJZRUh+7JTvBwftNYtcbIW8=
From: "bergner at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug ipa/114698] [12/13/14 regression] dcfldd produces wrong sha256
 sum on ppc64le and -O3 since r12-5244-g64f3e71c302b4a
Date: Thu, 11 Apr 2024 19:18:56 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: ipa
X-Bugzilla-Version: 14.0
X-Bugzilla-Keywords: wrong-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: bergner at gcc dot gnu.org
X-Bugzilla-Status: WAITING
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-114698-4-EjAgupu4kD@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-114698-4@http.gcc.gnu.org/bugzilla/>
References: <bug-114698-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114698

--- Comment #8 from Peter Bergner <bergner at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #6)
> Note this implementation of sha2.c is shared all over the place it seems =
and
> has this known issue ...

(In reply to Andrew Pinski from comment #4)
> (In reply to Andrew Pinski from comment #3)
> >         uint8_t buffer[SHA256_BLOCK_LENGTH];
> >=20
> >         W256 =3D (sha2_word32*)context->buffer;
> >=20
> > This is starting to smell like the code is violating strict aliasing ru=
les
> > ...
>=20
> The patch in  https://github.com/NetBSD/pkgsrc/issues/122  applies direct=
ly
> here too.

Thanks for the pointer, I'll try the patch and report back.  Jan's commit d=
oes
seem to make a change in the alias handling, so it very well could have exp=
osed
that type of problem in the sha2 routine.=