From: Jonathan Wakely <jwakely@redhat.com>
To: Jakub Jelinek <jakub@redhat.com>
Cc: xndcn <xndchn@gmail.com>, Xi Ruoyao <xry111@xry111.site>,
"H.J. Lu" <hjl.tools@gmail.com>,
GCC Patches <gcc-patches@gcc.gnu.org>,
libstdc++@gcc.gnu.org
Subject: Re: [PATCH] libstdc++: atomic: Add missing clear_padding in __atomic_float constructor
Date: Fri, 16 Feb 2024 15:15:24 +0000 [thread overview]
Message-ID: <CACb0b4kSc1AU30Yrz+vKVCjC5t=QgTLBeHvaMRywKOP=HkLLig@mail.gmail.com> (raw)
In-Reply-To: <Zc9suet5yfTm0k0A@tucnak>
On Fri, 16 Feb 2024 at 14:10, Jakub Jelinek wrote:
>
> On Fri, Feb 16, 2024 at 01:51:54PM +0000, Jonathan Wakely wrote:
> > Ah, although __atomic_compare_exchange only takes pointers, the
> > compiler replaces that with a call to __atomic_compare_exchange_n
> > which takes the newval by value, which presumably uses an 80-bit FP
> > register and so the padding bits become indeterminate again.
>
> __atomic_compare_exchange_n only works with integers, so I guess
> it is doing VIEW_CONVERT_EXPR (aka union-style type punning) on the
> argument.
>
> Do you have preprocessed source for the testcase?
Sent offlist.
next prev parent reply other threads:[~2024-02-16 15:15 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-08 1:01 xndcn
2024-01-15 0:45 ` [PING][PATCH] " xndcn
2024-01-15 3:46 ` [PATCH] " H.J. Lu
2024-01-16 9:53 ` xndcn
2024-01-16 10:12 ` Xi Ruoyao
2024-01-16 16:16 ` xndcn
2024-01-24 15:53 ` xndcn
2024-01-30 16:08 ` [PING][PATCH] " xndcn
2024-01-30 16:31 ` [PATCH] " Jonathan Wakely
2024-01-30 16:34 ` Jonathan Wakely
2024-01-30 16:50 ` Jakub Jelinek
2024-01-31 17:19 ` xndcn
2024-02-01 13:54 ` Jonathan Wakely
2024-02-02 16:52 ` xndcn
2024-02-16 12:38 ` Jonathan Wakely
2024-02-16 13:51 ` Jonathan Wakely
2024-02-16 14:10 ` Jakub Jelinek
2024-02-16 15:15 ` Jonathan Wakely [this message]
2024-03-14 15:13 ` Jonathan Wakely
2024-03-25 15:42 ` [PING][PATCH] " xndcn
2024-02-19 7:55 ` [PATCH] c-family, c++: Fix up handling of types which may have padding in __atomic_{compare_}exchange Jakub Jelinek
2024-02-20 0:12 ` Jason Merrill
2024-02-20 0:51 ` Jakub Jelinek
2024-02-20 8:01 ` Richard Biener
2024-02-20 10:02 ` [PATCH] c-family, c++, v2: " Jakub Jelinek
2024-02-20 10:11 ` Richard Biener
2024-02-20 10:27 ` Jakub Jelinek
2024-03-07 0:00 ` Jason Merrill
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CACb0b4kSc1AU30Yrz+vKVCjC5t=QgTLBeHvaMRywKOP=HkLLig@mail.gmail.com' \
--to=jwakely@redhat.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=hjl.tools@gmail.com \
--cc=jakub@redhat.com \
--cc=libstdc++@gcc.gnu.org \
--cc=xndchn@gmail.com \
--cc=xry111@xry111.site \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).