[patch] Do not bpstat_clear_actions on throw_exception

[Jan Kratochvil <jan.kratochvil@redhat.com>]

Hi,

as discussed here recently throw_exception does various unwised side effects.
This patch is a pre-requisite for the entryval patchset as unavailable entry
values is a normal caught silent exception there but it now stops any commands
execution.

This function was there already during initial import of GDB to CVS.  I do not
see its reason as any uncaught exception throws through bpstat_do_actions_1
and thus terminates the bpstat evaluation anyway.

And it the exception is caught there it is wrong to stop the commands
execution.

There was also the reset of bpstat->commands but I do not find it related:

http://sourceware.org/ml/gdb-patches/2003-12/msg00350.html
RFA: protect breakpoint commands from being freed
http://sourceware.org/ml/gdb-cvs/2003-12/msg00136.html
commit 79dbd81d5190cb413c7c44fdf00a858576f14e7e
Author: Jim Blandy <jimb@codesourcery.com>
Date:   Mon Dec 22 03:43:19 2003 +0000

    * breakpoint.c (bpstat_do_actions): To ensure that
    clear_proceed_status doesn't free the command tree we're
    evaluating out from under us, zero the bpstat's pointer to it, and
    take care of freeing it ourselves.
    * cli/cli-script.c (make_cleanup_free_command_lines): Make this
    function externally visible.
    * cli/cli-script.h (make_cleanup_free_command_lines): New
    declaration.

No regressions on {x86_64,x86_64-m32,i686}-fedora16pre-linux-gnu.


Thanks,
Jan


gdb/
2011-08-05  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* breakpoint.c (bpstat_clear_actions): Remove.
	* breakpoint.h (bpstat_clear_actions): Remove.
	* exceptions.c (throw_exception): Remove variable tp, its
	initialization and the call of bpstat_clear_actions.

--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -3186,23 +3186,6 @@ bpstat_num (bpstat *bsp, int *num)
   return 1;
 }
 
-/* Modify BS so that the actions will not be performed.  */
-
-void
-bpstat_clear_actions (bpstat bs)
-{
-  for (; bs != NULL; bs = bs->next)
-    {
-      decref_counted_command_line (&bs->commands);
-      bs->commands_left = NULL;
-      if (bs->old_val != NULL)
-	{
-	  value_free (bs->old_val);
-	  bs->old_val = NULL;
-	}
-    }
-}
-
 /* Called when a command is about to proceed the inferior.  */
 
 static void
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -895,9 +895,6 @@ extern int bpstat_num (bpstat *, int *);
    command loop).  */
 extern void bpstat_do_actions (void);
 
-/* Modify BS so that the actions will not be performed.  */
-extern void bpstat_clear_actions (bpstat);
-
 /* Implementation:  */
 
 /* Values used to tell the printing routine how to behave for this
--- a/gdb/exceptions.c
+++ b/gdb/exceptions.c
@@ -207,22 +207,9 @@ exceptions_state_mc_action_iter_1 (void)
 void
 throw_exception (struct gdb_exception exception)
 {
-  struct thread_info *tp = NULL;
-
   quit_flag = 0;
   immediate_quit = 0;
 
-  if (!ptid_equal (inferior_ptid, null_ptid))
-    tp = find_thread_ptid (inferior_ptid);
-
-  /* Perhaps it would be cleaner to do this via the cleanup chain (not sure
-     I can think of a reason why that is vital, though).  */
-  if (tp != NULL)
-    {
-      /* Clear queued breakpoint commands.  */
-      bpstat_clear_actions (tp->control.stop_bpstat);
-    }
-
   do_cleanups (ALL_CLEANUPS);
 
   /* Jump to the containing catch_errors() call, communicating REASON