From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sverre Rabbelier <srabbelier@gmail.com>
Subject: Re: [PATCH] compat: helper for detecting unsigned overflow
Date: Thu, 10 Feb 2011 13:11:17 +0100
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References: <1286263450-5372-1-git-send-email-kusmabite@gmail.com> <20110210093536.GB365@elie>
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Cc: git@vger.kernel.org, Erik Faye-Lund <kusmabite@gmail.com>,
	Jeff King <peff@peff.net>, Nicolas Pitre <nico@fluxnic.net>,
	Pierre Habouzit <madcoder@debian.org>,
	Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Jonathan Nieder <jrnieder@gmail.com>
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Heya,

On Thu, Feb 10, 2011 at 10:35, Jonathan Nieder <jrnieder@gmail.com> wro=
te:
>        unsigned_add_overflows(a, b)

> Define such a macro, expanding roughly to ((a) < UINT_MAX - (b)).
> Because the expansion uses each argument only once outside of sizeof(=
)
> expressions, it is safe to use with arguments that have side effects.

> +#define unsigned_add_overflows(a, b) \
> + =C2=A0 =C2=A0((b) > maximum_unsigned_value_of_type(a) - (a))

I'm confused, you say you won't use it twice, and then you do use it tw=
ice?

--=20
Cheers,

Sverre Rabbelier