public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "alvinhochun at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/104862] extern thread_local (emutls) code crashes with ASLR on Windows
Date: Thu, 12 May 2022 14:12:46 +0000 [thread overview]
Message-ID: <bug-104862-4-OLlkY3bpmc@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-104862-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104862
Alvin Wong <alvinhochun at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |ebotcazou at gcc dot gnu.org
--- Comment #1 from Alvin Wong <alvinhochun at gmail dot com> ---
I found from https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64697#c25 that there
was a change that seems related to the issue observed in this report. Can
anyone check?
> The master branch has been updated by Eric Botcazou <ebotcazou@gcc.gnu.org>:
>
> https://gcc.gnu.org/g:021ad8e5cf9ab66e1a0a41dce3a54586facb86e0
>
> commit r12-4036-g021ad8e5cf9ab66e1a0a41dce3a54586facb86e0
> Author: Eric Botcazou <ebotcazou@adacore.com>
> Date: Fri Oct 1 10:49:34 2021 +0200
>
> Fix PR c++/64697 at -O1 or above
>
> The BFD fix eliminates the link failure and working code is generated at
> -O0, but _not_ when optimization is enabled because the optimizer
> changes:
>
> movq .refptr._ZTH1s(%rip), %rax
> testq %rax, %rax
> je .L2
> call _ZTH1s
>
> into:
>
> leaq _ZTH1s(%rip), %rax
> testq %rax, %rax
> je .L2
> call _ZTH1s
>
> and the leaq now also gets the relocation overflow. So the fix is to
> teach legitimate_pic_address_disp_p to reject the transformation when
> the symbol is an external weak function, which yields:
>
> cmpq $0, .refptr._ZTH1s(%rip)
> je .L2
> call _ZTH1s
>
> and the cmpq keeps a relocation that does not overflow.
>
> gcc/
> PR c++/64697
> * config/i386/i386.c (legitimate_pic_address_disp_p): For
> PE-COFF do
> not return true for external weak function symbols in medium
> model.
next prev parent reply other threads:[~2022-05-12 14:12 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-10 9:07 [Bug c++/104862] New: " alvinhochun at gmail dot com
2022-05-12 14:12 ` alvinhochun at gmail dot com [this message]
2022-05-12 15:01 ` [Bug target/104862] " ebotcazou at gcc dot gnu.org
2022-06-30 10:38 ` ebotcazou at gcc dot gnu.org
2022-10-14 10:31 ` ebotcazou 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-104862-4-OLlkY3bpmc@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).