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 E0F44385AC33; Tue, 25 Oct 2022 15:26:05 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E0F44385AC33
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1666711568;
	bh=FupckYBAU4/TAKn5oVqicaW4wZsq3iAv1Yy98zt0lnw=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=uQjvfX2H6rAyNbnONHBafpddOSTfj6UGk94MRSG3pZXdgz3AVTXUatHdpRr6w/nkN
	 wFyB2idRVZ7CBtqmF+2dtK2bTzn0GcKokUf8+rp1vpoPGwcuC0wWR8rKVPvZBMgpwR
	 g6527MSdWIGIBTFBmTC0ttEjBINo+Tp21Faa3bSY=
From: "hjl.tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/102989] Implement C2x's n2763 (_BitInt)
Date: Tue, 25 Oct 2022 15:25:55 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c
X-Bugzilla-Version: 12.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: enhancement
X-Bugzilla-Who: hjl.tools at gmail dot com
X-Bugzilla-Status: NEW
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-102989-4-ImHo7LD2qC@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-102989-4@http.gcc.gnu.org/bugzilla/>
References: <bug-102989-4@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=3D102989

--- Comment #12 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Jakub Jelinek from comment #11)
> The x86-64 psABI has been changed for this:
> https://gitlab.com/x86-psABIs/x86-64-ABI/-/commit/
> 8ca45392570e96920f8a15d903d6122f6d263cd0
> but the state of the padding bits isn't mentioned there anywhere.

It was done on purpose.  Here are discussions about padding:

https://reviews.llvm.org/D108643

> Also, not sure I understand the
> \texttt{_BitInt(N)} types are byte-aligned to the next greatest power-of-2
> up to 64 bits.
> sentence because for N <=3D 64 there are different rules that apply (size=
 and
> alignment
> same as smallest standard integral type that can contain them) and so IMHO
> it should just
> say that the N > 64 bit-precise types are 64-bit aligned.

It sounds reasonable.=