[Bug ada/35284] Branch to 0x0 from Ada run-time

["laurent at guerby dot net" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #25 from laurent at guerby dot net  2008-04-01 19:40 -------
The binder will generate a call to Set_Globals
      pragma Import (C, Set_Globals, "__gnat_set_globals");

      Set_Globals
        (Main_Priority            => -1,
         Time_Slice_Value         => -1,
         WC_Encoding              => 'b',
         Locking_Policy           => ' ',
         Queuing_Policy           => ' ',
         Task_Dispatching_Policy  => ' ',
         Restrictions             => Restrictions'Address,
         Interrupt_States         => Interrupt_States'Address,
         Num_Interrupt_States     => 0,
         Unreserve_All_Interrupts => 0,
         Exception_Tracebacks     => 0,
         Zero_Cost_Exceptions     => 1,
         Detect_Blocking          => 0);


That should set the following global in s-taskin.adb:

   Main_Priority : Integer;
   pragma Import (C, Main_Priority, "__gl_main_priority");
   --  Priority for main task. Note that this is of type Integer, not
   --  Priority, because we use the value -1 to indicate the default
   --  main priority, and that is of course not in Priority'range.

Which is checked in System.tasking.initialize

      --  Initialize Environment Task

      if Main_Priority = Unspecified_Priority then
         Base_Priority := Default_Priority;
      else
         Base_Priority := Priority (Main_Priority);
      end if;

Default_Priority is defined in system-rtems.ads :

   Default_Priority : constant Priority := 122;

so my advice is breakpoint on the if above and see what happens. double check
that you compile using the right system.ads.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35284