public inbox for gcc-patches@gcc.gnu.org
 help / color / mirror / Atom feed
From: Joseph Myers <joseph@codesourcery.com>
To: Qing Zhao <qing.zhao@oracle.com>
Cc: jakub Jelinek <jakub@redhat.com>,
	richard Biener <rguenther@suse.de>,
	Kees Cook <keescook@chromium.org>,
	gcc Patches <gcc-patches@gcc.gnu.org>,
	Nathan Sidwell <Nathan@acm.org>, martin Sebor <msebor@gmail.com>
Subject: Re: [[GCC13][Patch][V3] 1/2] Add a new option -fstrict-flex-array[=n] and new attribute strict_flex_array
Date: Wed, 31 Aug 2022 17:21:35 +0000	[thread overview]
Message-ID: <alpine.DEB.2.22.394.2208311719200.498823@digraph.polyomino.org.uk> (raw)
In-Reply-To: <FE1A2F0B-5306-46A3-A543-6F7632138B15@oracle.com>

[-- Attachment #1: Type: text/plain, Size: 1007 bytes --]

On Wed, 31 Aug 2022, Qing Zhao via Gcc-patches wrote:

> > "a GNU extension" suggests a particular language feature, but I think 
> > you're actually referring here to a whole language version rather than an 
> > individual feature.
> 
> Is “not supported by GNU extension GNU89” better?

There are no existing diagnostics referring to GNU89 at all.  I don't 
think "GNU extension" needs to be mentioned in that diagnostic, but I also 
think that having that diagnostic at all is ill-conceived.

> > In any case, -std=gnu89 supports flexible array members.
> 
> Yes, but only [0],[1] are supported as flexible array members.  The C99 
> flexible array member [] is not supported by GNU89, right?

C99 flexible array members are fully supported in GNU89 mode.  In general, 
any feature from a new language version that doesn't affect code that was 
valid in previous versions is likely to be accepted as an extension with 
options for older language versions.

-- 
Joseph S. Myers
joseph@codesourcery.com

WARNING: multiple messages have this Message-ID
From: Joseph Myers <joseph@codesourcery.com>
To: Qing Zhao <qing.zhao@oracle.com>
Cc: jakub Jelinek <jakub@redhat.com>,
	richard Biener <rguenther@suse.de>,
	Kees Cook <keescook@chromium.org>,
	gcc Patches <gcc-patches@gcc.gnu.org>,
	Nathan Sidwell <Nathan@acm.org>, martin Sebor <msebor@gmail.com>
Subject: Re: [[GCC13][Patch][V3] 1/2] Add a new option -fstrict-flex-array[=n] and new attribute strict_flex_array
Date: Wed, 31 Aug 2022 17:21:35 +0000	[thread overview]
Message-ID: <alpine.DEB.2.22.394.2208311719200.498823@digraph.polyomino.org.uk> (raw)
Message-ID: <20220831172135.CJk8mwnWbXcdBiNaoTuOfU1F6zQoDacpZKixhZHK-QY@z> (raw)
In-Reply-To: <FE1A2F0B-5306-46A3-A543-6F7632138B15@oracle.com>

On Wed, 31 Aug 2022, Qing Zhao via Gcc-patches wrote:

> > "a GNU extension" suggests a particular language feature, but I think 
> > you're actually referring here to a whole language version rather than an 
> > individual feature.
> 
> Is “not supported by GNU extension GNU89” better?

There are no existing diagnostics referring to GNU89 at all.  I don't 
think "GNU extension" needs to be mentioned in that diagnostic, but I also 
think that having that diagnostic at all is ill-conceived.

> > In any case, -std=gnu89 supports flexible array members.
> 
> Yes, but only [0],[1] are supported as flexible array members.  The C99 
> flexible array member [] is not supported by GNU89, right?

C99 flexible array members are fully supported in GNU89 mode.  In general, 
any feature from a new language version that doesn't affect code that was 
valid in previous versions is likely to be accepted as an extension with 
options for older language versions.

-- 
Joseph S. Myers
joseph@codesourcery.com

  reply	other threads:[~2022-08-31 17:21 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-08-17 14:40 Qing Zhao
2022-08-17 14:40 ` [[GCC13][Patch][V3] 2/2] Use array_at_struct_end_p in __builtin_object_size [PR101836] Qing Zhao
2022-08-26  8:49   ` Richard Biener
2022-08-26 13:37     ` Qing Zhao
2022-08-26  8:48 ` [[GCC13][Patch][V3] 1/2] Add a new option -fstrict-flex-array[=n] and new attribute strict_flex_array Richard Biener
2022-08-26 13:47   ` Qing Zhao
2022-08-29  8:04     ` Richard Biener
2022-08-30 20:30 ` Fwd: " Qing Zhao
2022-08-30 20:30   ` Qing Zhao
2022-08-30 22:53   ` Joseph Myers
2022-08-31 14:00     ` Qing Zhao
2022-08-31 17:21       ` Joseph Myers [this message]
2022-08-31 17:21         ` Joseph Myers
2022-08-31 18:55         ` Qing Zhao
2022-08-31 19:24           ` Qing Zhao
2022-08-31 19:29           ` Joseph Myers
2022-08-31 19:29             ` Joseph Myers
2022-08-31 19:47             ` Qing Zhao
2022-08-31 19:52               ` Joseph Myers
2022-08-31 20:06                 ` Qing Zhao
2022-08-31 20:09                   ` Joseph Myers
2022-08-31 20:16                     ` Qing Zhao
2022-08-31 20:35                       ` Qing Zhao
2022-08-31 22:23                         ` Kees Cook
2022-09-01  6:11                           ` Richard Biener
2022-09-04 14:17                             ` Qing Zhao
2022-08-31 22:17                       ` Kees Cook

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=alpine.DEB.2.22.394.2208311719200.498823@digraph.polyomino.org.uk \
    --to=joseph@codesourcery.com \
    --cc=Nathan@acm.org \
    --cc=gcc-patches@gcc.gnu.org \
    --cc=jakub@redhat.com \
    --cc=keescook@chromium.org \
    --cc=msebor@gmail.com \
    --cc=qing.zhao@oracle.com \
    --cc=rguenther@suse.de \
    /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).