Re: SIGSEGV on recursive pthread_join

[Jeroen Dekkers]

On Mon, Jan 05, 2004 at 05:17:47PM +0100, Richard Guenther wrote:
> I'm experiencing a weird behavior with the NPTL threads, as that my
> application (sf.net/projects/glame) segfaults upon invocation of a
> pthread_join while the main process is currently joining the thread that
> tries to do the join. I.e.
> 
>   main:
>     pthread_join(thread1)
> 
>   thread1:
>     pthread_join(thread2)
>     ...
>     pthread_join(threadN)
> 
>   thread2..N:
>     maybe completed
> 
> and now as soon as thread1 joins thread2, the pthread_join() in main
> segfaults! The backtrace is not very helpful, it just shows pthread_join
> from /lib/tls/libpthread.so.0.  If using a libc with debugging symbols,
> the failure does _not_ occour!?  All threads were launched by main
> initially.

You can't join a thread more than once.

Jeroen Dekkers