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Date: Wed, 25 Jul 2007 18:26:48 +0100
From: Al Viro <viro@ftp.linux.org.uk>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       David Miller <davem@davemloft.net>, jeremy@goop.org, kaos@ocs.com.au,
       xyzzy@speakeasy.org, linux-kernel@vger.kernel.org,
       linux-arch@vger.kernel.org
Subject: Re: [PATCH][RFC] getting rid of stupid loop in BUG()
Message-ID: <20070725172648.GH27237@ftp.linux.org.uk>
References: <21803.1185331847@ocs10w.ocs.com.au> <46A6DB04.3000003@zytor.com> <46A6ECB7.7090208@goop.org> <20070724.232914.56812376.davem@davemloft.net> <alpine.LFD.0.999.0707250954400.3607@woody.linux-foundation.org> <20070725171956.GF27237@ftp.linux.org.uk> <46A786C7.9020604@zytor.com>
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On Wed, Jul 25, 2007 at 10:22:15AM -0700, H. Peter Anvin wrote:
> >> So we might as well keep the loop, since both are two-byte instructions 
> >> that tell gcc that it will never continue.
> > 
> > Umm...  Actually, we might be able to do something like
> > {
> > 	l: __builtin_trap();
> > 	static struct ... v __attribute__((section(...))) = { &&l, n, file };
> > }
> > 
> > except that it would need block-local labels and those are ugly (so's
> > &&<label>, while we are at it)...
> 
> I thought gcc was buggy when it came to passing &&labels to assembly.

Where do you see passing &&<label> to assembly?  More interesting question
is whether gcc believes it to be const...