public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libgcc/108727] gcc.dg/split-5.c fails on power 9 BE
Date: Wed, 08 Mar 2023 07:00:13 +0000	[thread overview]
Message-ID: <bug-108727-4-E5fpbjwnPE@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108727-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108727

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Kewen Lin <linkw@gcc.gnu.org>:

https://gcc.gnu.org/g:15b83b69ca99d97643075776ba94f2dd1f05b46e

commit r13-6545-g15b83b69ca99d97643075776ba94f2dd1f05b46e
Author: Kewen Lin <linkw@linux.ibm.com>
Date:   Wed Mar 8 00:57:21 2023 -0600

    libgcc, rs6000: Fix bump size for powerpc64 elfv1 ABI [PR108727]

    As PR108727 shows, when cleanup code called by the stack
    unwinder calls function _Unwind_Resume, it goes via plt
    stub like:

       function 00000000.plt_call._Unwind_Resume:

    => 0x0000000010003580 <+0>:     std     r2,40(r1)
       0x0000000010003584 <+4>:     ld      r12,-31760(r2)
       0x0000000010003588 <+8>:     mtctr   r12
       0x000000001000358c <+12>:    ld      r2,-31752(r2)
       0x0000000010003590 <+16>:    cmpldi  r2,0
       0x0000000010003594 <+20>:    bnectr+
       0x0000000010003598 <+24>:    b       0x100031a4
                                            <_Unwind_Resume@plt>

    It wants to save TOC base (r2) to r1 + 40, but we only
    bump the stack segment by 32 bytes as follows:

       stdu %r29,-32(%r3)

    It means the access is out of the stack segment allocated
    by __generic_morestack, once the touch area isn't writable
    like this failure shows, it would cause segment fault.

    So fix the bump size with one reasonable value PARAMS.

            PR libgcc/108727

    libgcc/ChangeLog:

            * config/rs6000/morestack.S (__morestack): Use PARAMS for new stack
            bump size.

  parent reply	other threads:[~2023-03-08  7:00 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-08 20:45 [Bug testsuite/108727] New: " seurer at gcc dot gnu.org
2023-03-01  6:03 ` [Bug testsuite/108727] " linkw at gcc dot gnu.org
2023-03-03 10:20 ` [Bug libgcc/108727] " linkw at gcc dot gnu.org
2023-03-03 12:58 ` amodra at gmail dot com
2023-03-06 11:01 ` linkw at gcc dot gnu.org
2023-03-08  7:00 ` cvs-commit at gcc dot gnu.org [this message]
2023-03-08  8:11 ` linkw 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-108727-4-E5fpbjwnPE@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).