On Saturday, 30 January 2021 at 12:28:16 UTC, Ali Çehreli wrote:
>
> I wonder whether doing something in the runtime is possible. For example, it may be more resilient and not crash when suspending a thread fails because the thread may be dead already.
>
> However, studying the runtime code around thread_detachThis three years ago, I had realized that like many things in computing, the whole stop-the-world is wishful thinking because there is no guarantee that your "please suspend this thread" request to the OS has succeeded. You get a success return code back but it means your request succeeded not that the thread was or will be suspended. (I may be misremembering this point but I know that the runtime requests things where OS does not give full guarantee for.)
>

OT. A thread that suspends itself will always happen (not taking fall through cases into account), if not, throw the OS away. If a thread suspends another thread, then you don't really know when that thread will be suspended. I would discourage that threads suspends other threads because that will open up a new world of race conditions. Some systems don't even allow it and its benefits are very limited.

Back to topic. I think that the generic solution even if it doesn't help you with your current implementation is to ban TLS all together. I think there have already been requests to remove TLS for druntime/phobos totally and I think this should definitely be done sooner than later. Also if you write a shared library in D, simply don't use TLS at all. This way it will not matter if a thread is registered by druntime or not. TLS is in my opinion a wart in computer science.

On Saturday, 30 January 2021 at 12:28:16 UTC, Ali Çehreli wrote:
> On 1/30/21 1:34 AM, Imperatorn wrote:
>
> > [...]
> should be
> > [...]
>
> I wonder whether doing something in the runtime is possible. For example, it may be more resilient and not crash when suspending a thread fails because the thread may be dead already.
>
> [...]

Will take a look at the e-book also. Didn't know there was a difference 👍