From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andreas Schwab <schwab@linux-m68k.org>
Subject: Re: [PATCH v4 1/2] refs.c: optimize check_refname_component()
Date: Sun, 01 Jun 2014 09:17:20 +0200
Message-ID: <m2k391drpb.fsf@linux-m68k.org>
References: <1401599865-14117-1-git-send-email-dturner@twitter.com>
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Cc: Michael Haggerty <mhagger@alum.mit.edu>,
	Junio C Hamano <gitster@pobox.com>, git@vger.kernel.org,
	David Turner <dturner@twitter.com>
To: David Turner <dturner@twopensource.com>
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	Turner's message of "Sun, 1 Jun 2014 01:17:44 -0400")
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David Turner <dturner@twopensource.com> writes:

> +static unsigned char refname_disposition[] = {
> +	1, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
> +	9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
> +	9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 0, 0, 0, 2, 1,
> +	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 0, 0, 0, 0, 9,
> +	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
> +	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 9, 0, 9, 0,
> +	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
> +	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 9, 9
> +};

> +		unsigned char ch = (unsigned char) *cp;
> +		char disp = refname_disposition[ch];

Undefined behaviour.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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