Re: [PATCH 0/4] reftable: fix out-of-memory errors on NonStop

From: Junio C Hamano <gitster@pobox.com>
Date: Dec 21, 2024, 17:43 UTC
Message-ID: <xmqqy109aq4a.fsf@gitster.g>
In-Reply-To: <BL3PR17MB6020D6CB8712F2C6F36FC8CFF4002@BL3PR17MB6020.namprd17.prod.outlook.com>

Randall Becker <randall.becker@nexbridge.ca> writes:

> Thank you for this series. I think the problem may not be limited
> only to NonStop based on the documented ambiguous behaviour of
> malloc.

Yes, an implementation is allowed to return NULL when asked to allocate 0 bytes. On the Git side, we sidestep the problem in exactly the opposite way---our malloc() wrapper makes another request to allocate 1-byte block after seeing NULL from a request for 0-byte allocation. The reftable code takes an approach to eliminate the need to requiest 0-sized allocation in the first place, which is an arguably more valid solution.

Thanks, both, for finding and fixing the issue.

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