Laurent indicated this is spurious on other targets but it is 100% regular on rtems so I thought I would give a backtrace.
It is calling pthread_kill(SIGABORT). This is the backtrace. ,.,. C974013 ACATS 2.5 88-01-01 00:00:00 ---- C974013 Asynchronous Select: Trigger is delay_until which completes before abortable part. Breakpoint 6, pthread_kill (thread=184614916, sig=6) at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/posix/src/pthreadkill.c:37 37 if ( !sig ) (gdb) bt #0 pthread_kill (thread=184614916, sig=6) at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/posix/src/pthreadkill.c:37 #1 0x00005600 in system.task_primitives.operations.abort_task ( t=<value optimized out>) at s-taprop.adb:1077 #2 0x00009950 in system.tasking.initialization.locked_abort_to_level ( self_id=0x90f10, t=0x93f50, l=<value optimized out>) at s-tasini.adb:505 #3 0x0000ed88 in system.tasking.async_delays.timer_server ( <_task>=<value optimized out>) at s-taasde.adb:382 #4 0x0000e0a4 in system.tasking.stages.task_wrapper (self_id=0x90f10) at s-tassta.adb:1151 #5 0x00052b38 in _Thread_Handler () at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/score/src/threadhandler.c:150 #6 0x00052a48 in _Thread_Evaluate_mode () at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/score/src/threadevaluatemode.c:53 This is the backtrace in rtems/powerpc from the abort (signo=6) when it is processed. (gdb) r Starting program: /home/joel/work-gnat/svn/gcc/gcc/testsuite/ada/acats/work-psim/tests/c9/c974013/c974013 ,.,. C974013 ACATS 2.5 88-01-01 00:00:00 ---- C974013 Asynchronous Select: Trigger is delay_until which completes before abortable part. Breakpoint 4, C_exception_handler (excPtr=0x715f20) at /home/joel/work-gnat/svn//rtems/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/vectors_init.c:119 119 nest++; (gdb) bt #0 C_exception_handler (excPtr=0x715f20) at /home/joel/work-gnat/svn//rtems/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/vectors_init.c:119 #1 0x00038f20 in wrap_call_global_handler_std () at /home/joel/work-gnat/svn//rtems/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/ppc_exc_asm_macros.h:596 #2 0xa5a5a5a5 in ?? () #3 0x00015880 in <__gnat_notify_handled_exception> () at a-exextr.adb:140 #4 0x00015508 in ada.exceptions.exception_propagation.propagate_exception (e=<value optimized out>, from_signal_handler=<value optimized out>) at a-exexpr.adb:116 #5 0x0001641c in <__gnat_raise_nodefer_with_msg> (e=0x3ad1331d) at a-except.adb:829 #6 0x000164b4 in <__gnat_raise_exception> (e=0x7ecf4, message={P_ARRAY = 0x80000, P_BOUNDS = 0x429f0005}) at a-except.adb:868 #7 0x00006740 in system.task_primitives.operations.abort_handler (sig=<value optimized out>) at s-taprop.adb:222 #8 0x00052420 in _POSIX_signals_Check_signal (api=0x6efef0, signo=6, is_global=<value optimized out>) at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/posix/src/psignalchecksignal.c:85 #9 0x0004f214 in _POSIX_signals_Post_switch_extension (the_thread=<value optimized out>) at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/posix/src/psignal.c:146 #10 0x00048d38 in _API_extensions_Run_postswitch () at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/score/src/apiext.c:103 #11 0x0004ae74 in _Thread_Dispatch () at /home/joel/work-gnat/svn//rtems/c/src/../../cpukit/score/src/threaddispatch.c:175 #12 0x00039768 in ppc_exc_wrapup (f=<value optimized out>) at /home/joel/work-gnat/svn//rtems/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/ppc_exc_hdl.c:97 #13 0x00038e28 in recover_check_twiddle_std_std () at /home/joel/work-gnat/svn//rtems/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/ppc_exc_asm_macros.h:596 Backtrace stopped: frame did not save the PC -- Summary: C974013 gives exception Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: ada AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: joel at gcc dot gnu dot org GCC target triplet: powerpc-rtems4.9 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37430