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Message-ID: <1520546351.23648.32.camel@hellion.org.uk>
Subject: Re: [PATCH] kernel.h: Skip single-eval logic on literals in
 min()/max()
From: Ian Campbell <ijc@hellion.org.uk>
To: Kees Cook <keescook@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
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Date: Thu, 08 Mar 2018 21:59:11 +0000
In-Reply-To: <20180308214045.GA6787@beast>
References: <20180308214045.GA6787@beast>
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On Thu, 2018-03-08 at 13:40 -0800, Kees Cook wrote:
> 
> +#define __min(t1, t2, x, y)						\
> +	__builtin_choose_expr(__builtin_constant_p(x) &&		\
> +			      __builtin_constant_p(y) &&		\
> +			      __builtin_types_compatible_p(t1, t2),	\
> +			      (t1)(x) < (t2)(y) ? (t1)(x) : (t2)(y),	\
> +			      __single_eval_min(t1, t2,			\
> +						__UNIQUE_ID(max1_),	\
> +						__UNIQUE_ID(max2_),	\

min1_ etc?

Ian.