Re: Possible issue with mutexes

[Herwig Hochleitner]

On 4/10/19 4:57 AM, Herwig Hochleitner wrote:
> Hello,
>
> I've recently created a semaphore type, based on mutex and condition 
> vars, for controlling parallelism in an elisp processor.
>
> The project went well, so far, but now that I attempted to pull out 
> this semaphore implementation and create a test for it, I've noticed 
> behavior, that leads me to believe, that emacs' thread and mutex 
> guarantees might not hold in all cases.
>
> When running the [test 
> case](https://github.com/webnf/semaphore.el/blob/306d5a84b99526213c3a7d367f8d8041961ea52a/test/emacs-semaphore-test.el), 
> you would expect `test/semaphore/active-count` to be 0 at the end of a 
> run, right? For me, it's wildly inconsistent at the end of a run and 
> seems to become desynchronized among worker threads. In this [example 
> run](https://hastebin.com/wigiwizabi.log) from my machine, it happens 
> to settle at 10.
>
> Am I doing this wrong, somehow?
>
> If not, could somebody help me file a report? First post on this ML ...
>
> kind regards

Argh .. found the bug in my code.

Sorry for the spam!


Since we are here already, let me ask you about this other issue, I had:

Waiting on a condition var or joining a thread on the main thread can 
freeze emacs totally dead. Like kill -9 dead.

Is this a known issue or should I investigate further?