From: Jeff King <peff@peff.net>
Date: Mon, 23 Sep 2019 22:27:00 GMT
Subject: Re: [PATCH] git: use COPY_ARRAY and MOVE_ARRAY in handle_alias()
Message-ID: <20190923222659.GA22645@sigill.intra.peff.net>
In-Reply-To: <d5eef24a-faa8-d6f3-c9e5-f13dc40219d4@web.de>

On Thu, Sep 19, 2019 at 10:48:30PM +0200, René Scharfe wrote:

> Use the macro COPY_ARRAY to copy array elements and MOVE_ARRAY to do the
> same for moving them backwards in an array with potential overlap.  The
> result is shorter and safer, as it infers the element type automatically
> and does a (very) basic type compatibility check for its first two
> arguments.
> 
> These cases were missed by Coccinelle and contrib/coccinelle/array.cocci
> because the type of the elements is "const char *", not "char *", and
> the rules in the semantic patch cautiously insist on the sizeof operator
> being used on exactly the same type to avoid generating transformations
> that introduce subtle bugs into tricky code.

Another good reason to use "sizeof(var)" instead of sizeof(type)". :)

The patch looks good.

-Peff