public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "stsp at users dot sourceforge.net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/103502] -Wstrict-aliasing=3 doesn't warn on what is documented as UB
Date: Tue, 30 Nov 2021 21:41:35 +0000	[thread overview]
Message-ID: <bug-103502-4-ZyjI3X3PzD@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103502-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103502

--- Comment #4 from Stas Sergeev <stsp at users dot sourceforge.net> ---
(In reply to Andrew Pinski from comment #3)
> Because GCC can optimize that pun+dereference pattern without _not_ breaking

Did you mean to say "without breaking the code"?
I will assume it is the case:

> the code, GCC decided it should not warn with =3.

So there is no breakage then?
Can I trust this no-warning?
Or what did the above "not" meant?

  parent reply	other threads:[~2021-11-30 21:41 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-30 17:22 [Bug c/103502] New: " stsp at users dot sourceforge.net
2021-11-30 21:20 ` [Bug c/103502] " pinskia at gcc dot gnu.org
2021-11-30 21:30 ` stsp at users dot sourceforge.net
2021-11-30 21:34 ` pinskia at gcc dot gnu.org
2021-11-30 21:41 ` stsp at users dot sourceforge.net [this message]
2021-11-30 22:07 ` stsp at users dot sourceforge.net
2021-12-01  0:28 ` egallager at gcc dot gnu.org
2021-12-01  1:26 ` stsp at users dot sourceforge.net

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-103502-4-ZyjI3X3PzD@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).