Bug 6116 – May not join spawn()'ed threads

Version: 2.053 The command line: ~/dmd2.053/linux/bin64/dmd deneme.d -ofdeneme -unittest -J. -w Although I have multiple threads spawning each other here, I also had problems with just a single thread spawned from main. I wanted to keep this example as it exposes many different outputs for me. import std.stdio; import std.concurrency; import core.thread; void foo() { foreach (i; 0 .. 5) { Thread.sleep(dur!"msecs"(500)); writeln(i, " foo"); } } void intermediate3() { spawn(&foo); writeln("intermediate3 done"); } void intermediate2() { spawn(&intermediate3); writeln("intermediate2 done"); } void intermediate() { spawn(&intermediate2); writeln("intermediate done"); } void main() { spawn(&intermediate); writeln("main done"); } 1) ThreadException: $ time ./deneme main done intermediate done intermediate2 done intermediate3 done core.thread.ThreadException@src/core/thread.d(866): Unable to join thread ---------------- ---------------- real 0m0.003s user 0m0.000s sys 0m0.000s 2) No output from foo() (foo() is not joined) $ time ./deneme main done intermediate done intermediate2 done intermediate3 done real 0m0.003s user 0m0.000s sys 0m0.000s 3) Segmentation fault: $ time ./deneme main done intermediate done Segmentation fault real 0m0.003s user 0m0.000s sys 0m0.000s 4) Expected behavior: $ time ./deneme main done intermediate done intermediate2 done intermediate3 done 0 foo 1 foo 2 foo 3 foo 4 foo

Apparently I clipped the timings for the last run. When it joins successfully, the program takes long, seemingly waiting for the foo() thread: $ time ./deneme main done intermediate done intermediate2 done intermediate3 done 0 foo 1 foo 2 foo 3 foo 4 foo real 0m2.504s user 0m0.000s sys 0m0.000s

What's likely happening is that the app is terminating before the new threads actually start, so they aren't marked isRunning when the wait loop occurs. The fix for this will likely be to add a status field where a thread may be marked as ready, starting, running, and terminated.

Run with 2.059 Win32: PS E:\DigitalMars\dmd2\samples> rdmd bug main done intermediate done intermediate2 done intermediate3 done 0 foo 1 foo 2 foo 3 foo 4 foo PS E:\DigitalMars\dmd2\samples>

Same here: This bug seems to have been fixed by other changes.

Closing this then. Please reopen if the bug resurfaces.