mysterious hang in pthread_create

[Kostik Belousov]

On Fri, Aug 29, 2008 at 05:18:18PM +0300, Andriy Gapon wrote:
> 
> Kostik, thanks!
> 
> on 29/08/2008 17:10 Kostik Belousov said the following:
> > I am wondering why did you not fixed it youself with all this information.
> 
> I am wondering that myself now :-)
> I got bogged in rtld details and simply didn't think about the solution
> of doing setthreaded earlier.
> 
> I will try your patch a couple of hours later.
> BTW, a forward question - should this patch help in the case of an
> exception thrown (and caught) before main(), i.e. in constructors of
> static/global objects?
If the objects are from the executable, then yes. I do not know about
present situation, but some time ago g++ and several other compilers
called ctr for global objects from the main() function. Regardeless
of this, init for main executable shall be called after init for
dependencies is finished. See initlist_add_objects().

On the other hand, ctr calls from linked dso may get fixed in regard
of exception throwing, or may not, depending on the relative order of
the dso loading against libthr.

> 
> > Anyway, patch below seems to work for me. David may have an opinion on
> > the change.
> > 
> > diff --git a/lib/libthr/thread/thr_init.c b/lib/libthr/thread/thr_init.c
> > index f96bba9..785d610 100644
> > --- a/lib/libthr/thread/thr_init.c
> > +++ b/lib/libthr/thread/thr_init.c
> > @@ -355,6 +355,9 @@ _libpthread_init(struct pthread *curthread)
> >  		if (_thread_event_mask & TD_CREATE)
> >  			_thr_report_creation(curthread, curthread);
> >  	}
> > +
> > +	if (_thr_isthreaded() == 0)
> > +		_thr_setthreaded(1);
> >  }
> >  
> >  /*
> 
> 
> -- 
> Andriy Gapon
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