Subject: Re: [PATCH 1/3] usage: refactor die-recursion checks

From: Johannes Sixt <[email-masked]>
Date: Tue, 16 Apr 2013 16:13:56 +0200

Am 4/16/2013 15:01, schrieb Jeff King:
> On Tue, Apr 16, 2013 at 09:18:46AM +0200, Johannes Sixt wrote:
> 
>>> Yeah, that seems sane; my biggest worry was that it would create
>>> headaches for Windows folks, who would have to emulate pthread_key. But
>>> it seems like we already added support in 9ba604a.
>>
>> pthread_key is not a problem, but pthread_once is. It's certainly
>> solvable, but do we really have to?
> 
> I'm not clear on what you are suggesting. That we protect only the main
> thread from recursion, or that we drop the check entirely? Or that we
> implement thread-local storage for this case without using pthread_once?

Anything(*) that does not require pthread_once. A pthread_once
implementation on Windows would be tricky and voluminous and and on top of
it very likely to be done differently for gcc and MSVC. I don't like to go
there if we can avoid it.

(*) That includes doing nothing, but does not include ripping out the
recursion check, as it protects us from crashes.

-- Hannes