[fpc-devel] TThread.Terminate;

[Jonas Maebe]

On 22/08/2020 16:09, Martin via fpc-devel wrote:
> procedure TThread.Terminate;
> begin
>   FTerminated := True;
> end;
> 
> Should that not in some way deal with memory barriers? E.g.
> InterlockedExchange or similar?

Very important: InterlockedExchange is not a memory barrier, except on x86.

> And the same for the "Terminated" property, should that have a getter to
> do the same?
> 
> As it stands, afaik a thread could get the "Terminate" flag with an
> unknown delay?

It's not a semaphore/signal, it's just a field. It will never be
instantaneous since it can only have an effect once the target thread
actually tries to read it. Wrapping it in a bunch of synchronisation
primitives will make the whole system slower with no real benefit.


Jonas