From: Jonny Grant <jg@jguk.org>
To: gcc-help@gcc.gnu.org, Gabriel Ravier <gabravier@gmail.com>
Cc: Xi Ruoyao <xry111@xry111.site>, Jonathan Wakely <jwakely.gcc@gmail.com>
Subject: Re: std::string add nullptr attribute
Date: Mon, 20 Feb 2023 11:44:31 +0000 [thread overview]
Message-ID: <8e65f974-daab-0b17-472a-4ee679885174@jguk.org> (raw)
In-Reply-To: <7e54f0b6-0c58-e340-46a3-b46fa321a201@inria.fr>
On 20/02/2023 11:18, Marc Glisse wrote:
> On Mon, 20 Feb 2023, Gabriel Ravier via Gcc-help wrote:
>
>> This is the kind of thing that makes me wonder why there isn't some kind of `__builtin_unreachable_do_not_optimize()` builtin that allows one to mark places in code that should never be reached and should thus be warned about if such a thing happens while at the same time never doing any optimization on the basis of the presence of the call.
>
> -fsanitize=unreachable -fsanitize=null and others prevent the kind of optimization you are worried about.
>
Unfortunately santizer is only at runtime. I'm seeking build time warnings. Sharing my example:
https://godbolt.org/z/c7b17nMGd
Execution build compiler returned: 0
Program returned: 139
/app/example.cpp:4:10: runtime error: load of null pointer of type 'const char'
Regards, Jonny
next prev parent reply other threads:[~2023-02-20 11:44 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-09 13:26 Jonny Grant
2023-02-09 14:56 ` Jonathan Wakely
2023-02-09 16:30 ` Xi Ruoyao
2023-02-09 17:52 ` Jonathan Wakely
2023-02-10 21:30 ` Jonny Grant
2023-02-10 22:03 ` Jonathan Wakely
2023-02-10 22:38 ` Jonny Grant
2023-02-11 0:32 ` Jonathan Wakely
2023-02-13 22:02 ` Jonny Grant
2023-02-19 20:43 ` Jonny Grant
2023-02-19 21:33 ` Jonny Grant
2023-02-20 10:26 ` Xi Ruoyao
2023-02-20 10:37 ` Jonathan Wakely
2023-02-20 10:54 ` Xi Ruoyao
2023-02-20 11:10 ` Gabriel Ravier
2023-02-20 11:18 ` Marc Glisse
2023-02-20 11:28 ` Segher Boessenkool
2023-02-20 12:00 ` Jonny Grant
2023-02-20 14:50 ` Gabriel Ravier
2023-02-20 11:44 ` Jonny Grant [this message]
2023-02-21 15:02 ` Jonny Grant
2023-02-20 11:38 ` Jonny Grant
2023-02-20 11:30 ` Jonny Grant
2023-02-20 12:59 ` Xi Ruoyao
2023-02-20 13:44 ` Jonathan Wakely
2023-02-20 19:21 ` Jonny Grant
2023-02-20 19:35 ` Jonathan Wakely
2023-02-20 19:39 ` Jonny Grant
2023-02-22 20:27 ` Jonny Grant
2023-02-21 15:04 ` Jonny Grant
2023-02-21 22:48 ` Jonny Grant
2023-03-04 15:00 ` Jonny Grant
2023-02-20 11:25 ` Jonny Grant
2023-03-12 22:10 ` Jonny Grant
2023-03-13 10:10 ` Jonathan Wakely
2023-03-13 19:55 ` Jonny Grant
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=8e65f974-daab-0b17-472a-4ee679885174@jguk.org \
--to=jg@jguk.org \
--cc=gabravier@gmail.com \
--cc=gcc-help@gcc.gnu.org \
--cc=jwakely.gcc@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).