linux-kernel - Re: hlist_for_each_entry && pos (Was: task_work

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 12 Apr 2012 06:02:45 +0100
From:	Al Viro <viro@...IV.linux.org.uk>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Oleg Nesterov <oleg@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	David Howells <dhowells@...hat.com>,
	David Smith <dsmith@...hat.com>,
	"Frank Ch. Eigler" <fche@...hat.com>,
	Larry Woodman <lwoodman@...hat.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Tejun Heo <tj@...nel.org>, linux-kernel@...r.kernel.org
Subject: Re: hlist_for_each_entry && pos (Was: task_work_queue)

On Wed, Apr 11, 2012 at 09:39:29PM -0700, Linus Torvalds wrote:

> The sad part is that if we allow that, we also get that *other* insane
> C99 variable thing - mixing variables and code.
> 
> I *like* getting warnings for confused people who start introducing
> variables in the middle of blocks of code. That's not well-contained
> like the loop variable.
> 
> That said, most of the stuff in C99 are extensions that we used long
> before C99, so I guess we might as well just add the stupid flag. And
> discourage people from mixing declarations and code other ways (sparse
> etc).

	Yes, but... -std=gnu99 will break one of your pet extensions -
(struct foo){0,1,2} will cease to be accepted in initializers of
static storage duration objects (and -std=c99 will break a *lot* more
than that).  I wouldn't mind going for that (it's not a terribly large
patch, at least it wasn't about a year ago when I've looked at that),
but IIRC you really insisted on using that one...  It mostly boiled
down to things like
-       .lock           = __SPIN_LOCK_UNLOCKED(init_fs.lock),
+       .lock           = __SPIN_LOCK_INITIALIZER(init_fs.lock),
etc.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/