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From: Rusty Russell <rusty@rustcorp.com.au>
To: "Jan Beulich" <JBeulich@novell.com>
Subject: Re: [PATCH] fix BUILD_BUG_ON() and a couple of bogus uses of it
Date: Tue, 22 Sep 2009 16:15:30 +0930
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Cc: linux-kernel@vger.kernel.org, Ben Elliston <bje@air.net.au>
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On Wed, 19 Aug 2009 01:29:25 am Jan Beulich wrote:
> Note that in the gfp.h, kmemcheck.h, and virtio_config.h cases
> MAYBE_BUILD_BUG_ON() really just serves documentation purposes - even
> if the expression is compile time constant (__builtin_constant_p()
> yields true), the array is still deemed of variable length by gcc, and
> hence the whole expression doesn't have the intended effect.

How annoying.  A gcc build assert extension would be great here?

Thanks,
Rusty.