https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83613
--- Comment #4 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> --- (In reply to Dominique d'Humieres from comment #3) > > Can you try this and report: > > ... > > It does not work without the patch > > --- ../_clean/libgfortran/io/unit.c 2017-12-14 10:02:30.000000000 +0100 > +++ libgfortran/io/unit.c 2017-12-29 00:28:42.000000000 +0100 > @@ -706,8 +706,8 @@ init_units (void) > __gthread_mutex_unlock (&u->lock); > } > /* The default internal units. */ > - u = insert_unit (GFC_INTERNAL_UNIT); > - u = insert_unit (GFC_INTERNAL_UNIT4); > +/* u = insert_unit (GFC_INTERNAL_UNIT); > + u = insert_unit (GFC_INTERNAL_UNIT4); */ > } > > > What is "fixed" by the lines > > u = insert_unit (GFC_INTERNAL_UNIT); > u = insert_unit (GFC_INTERNAL_UNIT4); > > ? We are creating two preconnected units for use exclusively for internal unit I/O. The unit structures are added to the treap. Later during an inquire that unit (its pointer is found) If a Unit is not found in the treap, it does not exist. The two units identified by GFC_INTERNAL_UNIT and GFC_INTERNAL_UNIT4 are exceptions, special reserved IDs. I dont understand why you did not have those two lines in your source tree. These were part of my previous patch committed.
