From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 14 Jun 2010 20:40:21 GMT
Subject: Re: [PATCH v2 2/3] textconv: support for blame
Message-ID: <7vfx0p9wlm.fsf@alter.siamese.dyndns.org>
In-Reply-To: <1275924218-20154-2-git-send-email-axel.bonnet@ensimag.imag.fr>

Axel Bonnet <axel.bonnet@ensimag.imag.fr> writes:

> @@ -86,16 +87,49 @@ struct origin {
> ...
> +static void fill_origin_blob(struct diff_options *opt,
> +			     struct origin *o, mmfile_t *file)
>  {
>  	if (!o->file.ptr) {
>  		enum object_type type;
>  		num_read_blob++;
> -		file->ptr = read_sha1_file(o->blob_sha1, &type,
> -					   (unsigned long *)(&(file->size)));
> +
> +		if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV) &&
> +		    textconv_object(o->path, o->blob_sha1, &file->ptr,
> +				    (size_t *) &file->size))

This cast is not correct, as there is no guarantee that your size_t and
typeof(mmfile_t.size) are compatible.  Depending on the gcc version, you
would get "dereferencing type-punned pointer will break strict-aliasing
rules" error.

The same issue exists in Clément's patch to builtin/cat-file.c.