2008-04-08 Eric Botcazou <ebotcazou@adacore.com>

	    Arnaud Charlet  <charlet@adacore.com>

	* s-osinte-linux-alpha.ads, s-osinte-linux-hppa.ads: Removed.

	s-taspri-posix-noaltstack.ads, s-linux.ads, s-linux-alpha.ads,
	s-linux-hppa.ads: New files. Disable alternate stack on ia64-hpux.

	* s-osinte-lynxos-3.ads,
	(Alternate_Stack): Remove when not needed. Simplify declaration
	otherwise.
	(Alternate_Stack_Size): New constant.

	s-osinte-mingw.ads, s-taprop-mingw.adb: Code clean up: avoid use of
	'Unrestricted_Access.

	* s-osinte-hpux.ads, s-osinte-solaris-posix.ads, s-osinte-aix.ads,
	s-osinte-lynxos.ads, s-osinte-freebsd.ads s-osinte-darwin.ads,
	s-osinte-tru64.ads, s-osinte-irix.ads, s-osinte-linux.ads,
	s-osinte-solaris.ads, s-osinte-vms.ads
	(SA_ONSTACK): New constant.
	(stack_t): New record type.
	(sigaltstack): New imported function.
	(Alternate_Stack): New imported variable.
	(Alternate_Stack_Size): New constant.

	* system-linux-x86_64.ads: (Stack_Check_Probes): Set to True.

	* s-taspri-lynxos.ads, s-taspri-solaris.ads, s-taspri-tru64.ads,
	s-taspri-hpux-dce.ads (Task_Address): New subtype of System.Address
	(Task_Address_Size): New constant size of System.Address
	(Alternate_Stack_Size): New constant.

	* s-taprop-posix.adb, s-taprop-linux.adb (Get_Stack_Attributes): Delete.
	(Enter_Task): Do not notify stack to System.Stack_Checking.Operations.
	Establish the alternate stack if the platform makes use of n alternate
	signal stack for stack overflows.
	(Create_Task): Take into account the alternate stack in the stack size.
	(Initialize): Save the address of the alternate stack into the ATCB for
	the environment task.
	(Create_Task): Fix assertions for NPTL library (vs old LinuxThreads).

	* s-parame.adb (Minimum_Stack_Size): Increase value to 16K to

	* system-linux-x86.ads: (Stack_Check_Probes): Set to True.

	* s-intman-posix.adb: 
	(Initialize): Set SA_ONSTACK for SIGSEGV if the platform makes use of an
	alternate signal stack for stack overflows.

	* init.c (__gnat_adjust_context_for_raise, Linux version): On i386 and
	x86-64, adjust the saved value of the stack pointer if the signal was
	raised by a stack checking probe.
	(HP-UX section): Use global __gnat_alternate_stack as signal handler
	stack and only for SIGSEGV.
	(Linux section): Likewise on x86 and x86-64.
	[VxWorks section]
	(__gnat_map_signal): Now static.
	(__gnat_error_handler): Not static any more.
	(__gnat_adjust_context_for_raise): New function. Signal context
	adjustment for PPC && !VTHREADS && !RTP, as required by the zcx
	propagation circuitry.
	(__gnat_error_handler): Second argument of a sigaction handler is a
	pointer, not an int, and is unused.
	Adjust signal context before mapping to exception.
	Install signal handlers for LynxOS case.

	* s-taskin.ads (Common_ATCB): New field Task_Alternate_Stack.
	(Task_Id): Set size to Task_Address_Size
	(To_Task_id): Unchecked convert from Task_Address vice System.Address
	(To_Address): Unchecked convert to Task_Address vice System.Address

	* s-tassta.adb (Task_Wrapper): Define the alternate stack and save its
	address into the ATCB if the platform makes use of an alternate signal
	stack for stack overflows.
	(Free_Task): Add call to Finalize_Attributes_Link.
	Add argument Relative_Deadline to pass the value specified for
	the task. This is not yet used for any target.

	* s-tassta.ads (Create_Task): Add argument Relative_Deadline to pass
	the value specified for the task.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@134004 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 23 insertions, 1 deletions

diff --git a/gcc/ada/s-taprop-posix.adb b/gcc/ada/s-taprop-posix.adb
index 816bb50a7b6..5b677bf539f 100644
--- a/gcc/ada/s-taprop-posix.adb
+++ b/gcc/ada/s-taprop-posix.adb
@@ -73,6 +73,9 @@ package body System.Task_Primitives.Operations is
    use System.Parameters;
    use System.OS_Primitives;
 
+   Use_Alternate_Stack : constant Boolean := Alternate_Stack_Size /= 0;
+   --  Whether to use an alternate signal stack for stack overflows
+
    ----------------
    -- Local Data --
    ----------------
@@ -798,6 +801,19 @@ package body System.Task_Primitives.Operations is
       end loop;
 
       Unlock_RTS;
+
+      if Use_Alternate_Stack then
+         declare
+            Stack  : aliased stack_t;
+            Result : Interfaces.C.int;
+         begin
+            Stack.ss_sp    := Self_ID.Common.Task_Alternate_Stack;
+            Stack.ss_size  := Alternate_Stack_Size;
+            Stack.ss_flags := 0;
+            Result := sigaltstack (Stack'Access, null);
+            pragma Assert (Result = 0);
+         end;
+      end if;
    end Enter_Task;
 
    --------------
@@ -932,7 +948,8 @@ package body System.Task_Primitives.Operations is
       use System.Task_Info;
 
    begin
-      Adjusted_Stack_Size := Interfaces.C.size_t (Stack_Size);
+      Adjusted_Stack_Size :=
+         Interfaces.C.size_t (Stack_Size + Alternate_Stack_Size);
 
       if Stack_Base_Available then
 
@@ -1415,6 +1432,11 @@ package body System.Task_Primitives.Operations is
 
       Specific.Initialize (Environment_Task);
 
+      if Use_Alternate_Stack then
+         Environment_Task.Common.Task_Alternate_Stack :=
+           Alternate_Stack'Address;
+      end if;
+
       Enter_Task (Environment_Task);
 
       --  Install the abort-signal handler