Threading bugs

[Sean Kelly]

Tristam MacDonald wrote:
> Hmm, I don't see anything relevant in either the changelog or the news group (haven't finished searching the latter though).
> 
> I am not sure I understand, shouldn't all remaining objects have their destructors called when the program exits? What would happen if the object had a non trivial destructor (dispose of shared memory, flush an iostream, etc.)?

Running the dtors of all objects on exit is problematic.  Should they 
run before or after the module dtors?  What if they are run after the 
module dtors but the object in question relied on the module's dtor not 
yet having been run?  In Tango, uncollected objects not specifically 
cleaned up in a module dtor are not guaranteed to be collected for this 
reason.  An alternative would be to run a collection after main() exits 
as a part of the cleanup process.  This would get your Main object 
below, but it would slow the shutdown process for the sake of collecting 
only a very few objects, and I'm not sure it's worthwhile to do so.

> The point I don't understand, is why is this only the case when I am using threads? And I think the thread implementation may be a little buggy here anyway, why on earth would the assert statement below cause a 'Bus Error'?

I have no idea.  On Tango, your program outputs:

     starting
     In Thread

Here's the converted code:


     import tango.core.Thread;
     import tango.stdc.stdio;

     class Main
     {
     	this() {
     		printf("starting\n");

     		Thread worker = new Thread(&workerMain);
     		worker.start();
     	}
     	~this() {
     		printf("ending\n");
     	}

     	void workerMain()
     	{
     		printf("In Thread\n");
     	}

     	Thread worker;
     }

     int main()
     {
     	Main m = new Main();

     	return 0;
     }

Sean