From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: trim_common_tail bug?
Date: Sat, 15 Dec 2007 09:49:06 -0800
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	<20071215155150.GA24810@coredump.intra.peff.net>
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Cc: Linus Torvalds <torvalds@linux-foundation.org>, git@vger.kernel.org
To: Jeff King <peff@peff.net>
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In-Reply-To: <20071215155150.GA24810@coredump.intra.peff.net> (Jeff King's
	message of "Sat, 15 Dec 2007 10:51:50 -0500")
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Jeff King <peff@peff.net> writes:

> diff --git a/xdiff-interface.c b/xdiff-interface.c
> index 700def2..eb60e88 100644
> --- a/xdiff-interface.c
> +++ b/xdiff-interface.c
> @@ -124,6 +124,8 @@ static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
>  	for (i = 0, recovered = 0; recovered < trimmed && i <= ctx; i++) {
>  		while (recovered < trimmed && ap[recovered] != '\n')
>  			recovered++;
> +		if (recovered < trimmed && ap[recovered] == '\n')
> +			recovered++;
>  	}
>  	a->size -= (trimmed - recovered);
>  	b->size -= (trimmed - recovered);

Shoot.  Thanks for spotting.

Wouldn't it be enough to do:

  	for (i = 0, recovered = 0; recovered < trimmed && i <= ctx; i++) {
		while (recovered < trimmed && ap[recovered++] != '\n')
	        	; /* nothing */
	}

then (warning: I haven't had my coffee yet)?