On 11/02/2014 09:04 AM, Sean Kelly wrote:
> On Sunday, 2 November 2014 at 06:23:38 UTC, Ali Çehreli wrote:
>> Can I safely remove thread_joinAll()s if they are the last lines in
>> main()?
>
> It has always been the case. In fact, I have a comment in the body of
> Thread.start() explaining this potential race and explaining the need
> for certain operations in that function.
I've grepped for thread_joinAll calls in my examples and identified two
cases where I needed it at the end of main, both of which about the need
to "pull" thread_joinAll inside main's scope. Otherwise, the automatic
thread_joinAll call would happen after main's scope ends and it would be
too late in the following cases.
1) A scope(exit) should not unregister() before all threads finish.
2) A thread still uses an object tied to main's scope.
void main()
{
auto first = spawn(&player, "second");
register("first", first);
scope(exit) unregister("first"); // <-- (1)
// ...
immutable(int) i = 42;
spawn(&worker, &i); // <-- (2)
// ...
thread_joinAll(); // <-- justified
}
The thread_joinAll() at the end of main() above is justified to take
care of both of those cases.
Ali
