On Fri, Aug 29, 2014 at 10:40:57AM -0700, Richard Henderson wrote: > On 08/06/2014 03:05 AM, Varvara Rainchik wrote: > > * libgomp.h (gomp_thread): For non TLS case create thread data. > > * team.c (create_non_tls_thread_data): New function. > > > > > > --- > > diff --git a/libgomp/libgomp.h b/libgomp/libgomp.h > > index a1482cc..cf3ec8f 100644 > > --- a/libgomp/libgomp.h > > +++ b/libgomp/libgomp.h > > @@ -479,9 +479,15 @@ static inline struct gomp_thread *gomp_thread (void) > > } > > #else > > extern pthread_key_t gomp_tls_key; > > +extern struct gomp_thread *create_non_tls_thread_data (void); > > static inline struct gomp_thread *gomp_thread (void) > > { > > - return pthread_getspecific (gomp_tls_key); > > + struct gomp_thread *thr = pthread_getspecific (gomp_tls_key); > > + if (thr == NULL) > > + { > > + thr = create_non_tls_thread_data (); > > + } > > + return thr; > > } > > This should never happen.
I guess it can happen if you mix up explicit pthread_create and libgomp APIs. initialize_team will only initialize it in the initial thread, while if you use #pragma omp ... or omp_* calls from a thread created with pthread_create, in the !HAVE_TLS case pthread_getspecific will return NULL. Now, the patch doesn't handle that case completely though (and is badly formatted), the problem is that if we allocate in the !HAVE_TLS case in non-initial thread the TLS data, we want to free them again, so that would mean pthread_key_create with non-NULL destructor, and then we need to differentiate in between the 3 cases - key equal to &initial_thread_tls_data (would need to move out of the block context), no freeing needed, thread created by gomp_thread_start, no freeing needed, otherwise free. > The thread-specific data is set in gomp_thread_start and initialize_team. > > Where are you getting a call to gomp_thread that hasn't been through one of > those functions? Jakub