From: Dan McGee <dpmcgee@gmail.com>
Date: Tue, 19 May 2009 04:32:48 GMT
Subject: Re: [PATCH] Fix type-punning issues
Message-ID: <449c10960905182132h2c1b38b4jd28721adaeb38484@mail.gmail.com>
In-Reply-To: <7vy6t292ix.fsf@alter.siamese.dyndns.org>

On Tue, May 12, 2009 at 2:57 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Dan McGee <dpmcgee@gmail.com> writes:
>
>> In these two places we are casting part of our unsigned char sha1 array into
>> an unsigned int, which violates GCCs strict-aliasing rules (and probably
>> other compilers).
>
> Yay.
>

> It might make more sense to have one canonical
>
>        unsigned int hash_obj(const struct object *obj, unsigned int n)
>
> here, export it to object.h, and remove the one in decorate.c.
>
> Or am I missing something?

(argh: sorry Junio for sending the last reply to just you)

So due to me taking so long to resubmit, I see you committed a
stripped-down version of my patch. I had a patch just like this (minus
one newline diff), but it was in a series of 4 I will submit in just a
second.

The three remaining patches implement the above suggestion of having
one canonical "hash" function. However, the name changes to hash_char
and takes a unsigned char pointer rather than a struct object pointer
so we can use the same function for both insertion into the hashes as
well as lookup.

Looking forward to any feedback.

-Dan