From: Jeff King <peff@peff.net>
Date: Fri, 05 Sep 2025 13:15:13 GMT
Subject: Re: [PATCH v5] alloc: fix dangling pointer in alloc_state cleanup
Message-ID: <20250905131513.GB596956@coredump.intra.peff.net>
In-Reply-To: <xmqqjz2d7t2q.fsf@gitster.g>

On Thu, Sep 04, 2025 at 03:26:21PM -0700, Junio C Hamano wrote:

> Jeff King <peff@peff.net> writes:
> 
> > It's probably not worth going back and forth on this too much, but I
> > thought the happy medium was:
> >
> >   if (!s)
> > 	return;
> >
> > That is, it is perfectly reasonable and friendly for it to be a noop to
> > free-and-null a NULL value (either never initialized, or already freed).
> > The overkill was worrying about whether somebody passed in a NULL
> > double-pointer. I.e., doing:
> >
> >   alloc_state_free_and_null(&foo);
> >
> > is reasonable and should be idempotent
> 
> ... when foo == NULL, e.g., after alloc_state_free_and_null(&foo)
> has just successfully returned?

Exactly.

> I can by that argument with the reasoning in the updated log message
> below.  Does it good to everybody?

Yep, it looks good to me.

-Peff