From: ノウラ | Flare <nouraellm@gmail.com>
Date: Thu, 04 Sep 2025 13:25:57 GMT
Subject: Re: [PATCH v4] alloc: fix dangling pointer in alloc_state cleanup
Message-ID: <c8137063-c928-45a1-aae5-9de2b35e5150@gmail.com>
In-Reply-To: <xmqqh5xibqvu.fsf@gitster.g>

The point of the check was to avoid subtle crashes
aligning with defensive programming requirements.

If you lean more towards strict contract enforcement
Just say the word.

On 04/09/2025 09:47, Junio C Hamano wrote:
> "ノウラ | Flare via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
>> +void alloc_state_free_and_null(struct alloc_state **s_)
>>   {
>> +	struct alloc_state *s;
>> +
>> +	if (!s_ || !*s_) return;
> I still do not see the point of this check.  If the caller passes a
> NULL pointer, when they are expected to pass the address of a
> pointer variable so that the struct the pointer points at is cleared
> and freed, and the pointer variable is NULLed, it is called a
> programmer error and they deserve a segfault.  Why would it be
> better to sweep such an error under the rug by returning without
> anything?  It would delay discovery of such a bug, but for what
> gain?
>