public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "xry111 at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/110791] [12/13/14 Regression] arm: Wrong code with -Os -march=armv8.1-m.main
Date: Mon, 24 Jul 2023 11:29:47 +0000	[thread overview]
Message-ID: <bug-110791-4-GKDBN8OnAW@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110791-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110791

Xi Ruoyao <xry111 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |UNCONFIRMED
     Ever confirmed|1                           |0

--- Comment #3 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
(In reply to Alex Coplan from comment #2)
> (In reply to Xi Ruoyao from comment #1)
> > Isn't this a UB?
> > 
> >   while (p >= path && *p != '/')
> >     p--;
> > 
> > This will cause p to become "&main::path[0] - 1".  C23 6.5.6p9:
> 
> In this case, with the input given in main, I think p should end up pointing
> to main::path + 1 (since we pass in main::path + 2, and foo can only ever
> decrement p at most one below its parameter path).

Sorry, I misread the code.  I guess I need to drink some coffee now...

  parent reply	other threads:[~2023-07-24 11:29 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-24 10:51 [Bug rtl-optimization/110791] New: " acoplan at gcc dot gnu.org
2023-07-24 11:24 ` [Bug rtl-optimization/110791] " xry111 at gcc dot gnu.org
2023-07-24 11:27 ` acoplan at gcc dot gnu.org
2023-07-24 11:29 ` xry111 at gcc dot gnu.org [this message]
2023-07-24 13:09 ` wilco at gcc dot gnu.org
2023-07-24 13:23 ` rguenth at gcc dot gnu.org
2023-07-24 14:39 ` acoplan at gcc dot gnu.org
2023-07-24 15:14 ` [Bug middle-end/110791] " wilco at gcc dot gnu.org
2024-03-07 23:28 ` [Bug rtl-optimization/110791] [12/13/14 Regression] arm: Wrong code with -Os -march=armv8.1-m.main (maybe fmodulo-sched related) law at gcc dot gnu.org
2024-06-20  9:13 ` [Bug rtl-optimization/110791] [12/13/14/15 " rguenth at gcc dot gnu.org

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=bug-110791-4-GKDBN8OnAW@http.gcc.gnu.org/bugzilla/ \
    --to=gcc-bugzilla@gcc.gnu.org \
    --cc=gcc-bugs@gcc.gnu.org \
    /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).