From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 25 Jun 2007 06:18:33 GMT
Subject: Re: [PATCH] diff: round down similarity index
Message-ID: <7vir9co8ue.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <467EEEE6.3090100@lsrfire.ath.cx>

René Scharfe <rene.scharfe@lsrfire.ath.cx> writes:

> +static int similarity_index(struct diff_filepair *p)
> +{
> +	int result = p->score * 100.0 / MAX_SCORE;
> +
> +	/* Paranoia: guard against floating point rounding errors. */
> +	if (p->score == MAX_SCORE)
> +		result = 100;
> +	else if (result == 100)
> +		result = 99;
> +
> +	return result;
> +}

Why not simply do this?

        static int similarity_index(struct diff_filepair *p)
        {
                if (p->score == MAX_SCORE)
                        return 100;
                return p->score * 100 / MAX_SCORE;
        }

MAX_SCORE and p->score run up to 60000 and we assume int is at
least 32-bit, so I do not think there is no risk of overflowing.