gdb

	PR c++/9593:
	* thread.c (clear_thread_inferior_resources): Call
	delete_longjmp_breakpoint.
	* infrun.c (handle_inferior_event): Handle exception breakpoints.
	(handle_inferior_event): Likewise.
	(insert_exception_resume_breakpoint): New function.
	(check_exception_resume): Likewise.
	* inferior.h (delete_longjmp_breakpoint_cleanup): Declare.
	* infcmd.c (delete_longjmp_breakpoint_cleanup): No longer static.
	(step_1): Set thread's initiating frame.
	(until_next_continuation): New function.
	(until_next_command): Support exception breakpoints.
	(finish_command_continuation): Delete longjmp breakpoint.
	(finish_forward): Support exception breakpoints.
	* gdbthread.h (struct thread_info) <initiating_frame>: New field.
	* breakpoint.h (enum bptype) <bp_exception, bp_exception_resume,
	bp_exception_master>: New constants.
	(struct bpstat_what) <is_longjmp>: New field.
	(set_longjmp_breakpoint): Update.
	* breakpoint.c (create_exception_master_breakpoint): New function.
	(update_breakpoints_after_exec): Handle bp_exception_master.  Call
	create_exception_master_breakpoint.
	(print_it_typical): Handle bp_exception_master, bp_exception.
	(bpstat_stop_status): Handle bp_exception_master.
	(bpstat_what): Handle bp_exception_master, bp_exception,
	bp_exception_resume.
	(bptype_string): Likewise.
	(print_one_breakpoint_location): Likewise.
	(allocate_bp_location): Likewise.
	(set_longjmp_breakpoint): Handle exception breakpoints.  Change
	interface.
	(delete_longjmp_breakpoint): Handle exception breakpoints.
	(mention): Likewise.
	(struct until_break_command_continuation_args) <thread_num>: New
	field.
	(until_break_command_continuation): Call
	delete_longjmp_breakpoint.
	(until_break_command): Support exception breakpoints.
	(delete_command): Likewise.
	(breakpoint_re_set_one): Likewise.
	(breakpoint_re_set): Likewise.
gdb/testuite
	* gdb.java/jnpe.java: New file.
	* gdb.java/jnpe.exp: New file.
	* gdb.cp/nextoverthrow.exp: New file.
	* gdb.cp/nextoverthrow.cc: New file.

1 files changed, 177 insertions, 15 deletions

diff --git a/gdb/infrun.c b/gdb/infrun.c
index 1604e95..1bc00a4 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -45,6 +45,8 @@
 #include "language.h"
 #include "solib.h"
 #include "main.h"
+#include "dictionary.h"
+#include "block.h"
 #include "gdb_assert.h"
 #include "mi/mi-common.h"
 #include "event-top.h"
@@ -377,6 +379,7 @@ follow_fork (void)
      parent thread structure's run control related fields, not just these.
      Initialized to avoid "may be used uninitialized" warnings from gcc.  */
   struct breakpoint *step_resume_breakpoint = NULL;
+  struct breakpoint *exception_resume_breakpoint = NULL;
   CORE_ADDR step_range_start = 0;
   CORE_ADDR step_range_end = 0;
   struct frame_id step_frame_id = { 0 };
@@ -429,6 +432,8 @@ follow_fork (void)
 	    step_range_start = tp->control.step_range_start;
 	    step_range_end = tp->control.step_range_end;
 	    step_frame_id = tp->control.step_frame_id;
+	    exception_resume_breakpoint
+	      = clone_momentary_breakpoint (tp->control.exception_resume_breakpoint);
 
 	    /* For now, delete the parent's sr breakpoint, otherwise,
 	       parent/child sr breakpoints are considered duplicates,
@@ -439,6 +444,7 @@ follow_fork (void)
 	    tp->control.step_range_start = 0;
 	    tp->control.step_range_end = 0;
 	    tp->control.step_frame_id = null_frame_id;
+	    delete_exception_resume_breakpoint (tp);
 	  }
 
 	parent = inferior_ptid;
@@ -481,6 +487,8 @@ follow_fork (void)
 		    tp->control.step_range_start = step_range_start;
 		    tp->control.step_range_end = step_range_end;
 		    tp->control.step_frame_id = step_frame_id;
+		    tp->control.exception_resume_breakpoint
+		      = exception_resume_breakpoint;
 		  }
 		else
 		  {
@@ -534,6 +542,9 @@ follow_inferior_reset_breakpoints (void)
   if (tp->control.step_resume_breakpoint)
     breakpoint_re_set_thread (tp->control.step_resume_breakpoint);
 
+  if (tp->control.exception_resume_breakpoint)
+    breakpoint_re_set_thread (tp->control.exception_resume_breakpoint);
+
   /* Reinsert all breakpoints in the child.  The user may have set
      breakpoints after catching the fork, in which case those
      were never set in the child, but only in the parent.  This makes
@@ -771,6 +782,7 @@ follow_exec (ptid_t pid, char *execd_pathname)
   /* If there was one, it's gone now.  We cannot truly step-to-next
      statement through an exec(). */
   th->control.step_resume_breakpoint = NULL;
+  th->control.exception_resume_breakpoint = NULL;
   th->control.step_range_start = 0;
   th->control.step_range_end = 0;
 
@@ -2219,6 +2231,8 @@ static void insert_step_resume_breakpoint_at_sal (struct gdbarch *gdbarch,
 						  struct symtab_and_line sr_sal,
 						  struct frame_id sr_id);
 static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
+static void check_exception_resume (struct execution_control_state *,
+				    struct frame_info *, struct symbol *);
 
 static void stop_stepping (struct execution_control_state *ecs);
 static void prepare_to_wait (struct execution_control_state *ecs);
@@ -2340,6 +2354,7 @@ delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
     return 0;
 
   delete_step_resume_breakpoint (info);
+  delete_exception_resume_breakpoint (info);
   return 0;
 }
 
@@ -2364,6 +2379,7 @@ delete_step_thread_step_resume_breakpoint (void)
       struct thread_info *tp = inferior_thread ();
 
       delete_step_resume_breakpoint (tp);
+      delete_exception_resume_breakpoint (tp);
     }
   else
     /* In all-stop mode, delete all step-resume and longjmp-resume
@@ -4112,23 +4128,33 @@ process_event_stop_test:
 
 	ecs->event_thread->stepping_over_breakpoint = 1;
 
-	if (!gdbarch_get_longjmp_target_p (gdbarch)
-	    || !gdbarch_get_longjmp_target (gdbarch, frame, &jmp_buf_pc))
+	if (what.is_longjmp)
 	  {
-	    if (debug_infrun)
-	      fprintf_unfiltered (gdb_stdlog, "\
+	    if (!gdbarch_get_longjmp_target_p (gdbarch)
+		|| !gdbarch_get_longjmp_target (gdbarch,
+						frame, &jmp_buf_pc))
+	      {
+		if (debug_infrun)
+		  fprintf_unfiltered (gdb_stdlog, "\
 infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
-	    keep_going (ecs);
-	    return;
-	  }
+		keep_going (ecs);
+		return;
+	      }
 
-	/* We're going to replace the current step-resume breakpoint
-	   with a longjmp-resume breakpoint.  */
-	delete_step_resume_breakpoint (ecs->event_thread);
+	    /* We're going to replace the current step-resume breakpoint
+	       with a longjmp-resume breakpoint.  */
+	    delete_step_resume_breakpoint (ecs->event_thread);
 
-	/* Insert a breakpoint at resume address.  */
-	insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
+	    /* Insert a breakpoint at resume address.  */
+	    insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
+	  }
+	else
+	  {
+	    struct symbol *func = get_frame_function (frame);
 
+	    if (func)
+	      check_exception_resume (ecs, frame, func);
+	  }
 	keep_going (ecs);
 	return;
 
@@ -4137,9 +4163,54 @@ infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
 	  fprintf_unfiltered (gdb_stdlog,
 			      "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
 
-	gdb_assert (ecs->event_thread->control.step_resume_breakpoint
-		    != NULL);
-	delete_step_resume_breakpoint (ecs->event_thread);
+	if (what.is_longjmp)
+	  {
+	    gdb_assert (ecs->event_thread->control.step_resume_breakpoint
+			!= NULL);
+	    delete_step_resume_breakpoint (ecs->event_thread);
+	  }
+	else
+	  {
+	    /* There are several cases to consider.
+
+	       1. The initiating frame no longer exists.  In this case
+	       we must stop, because the exception has gone too far.
+
+	       2. The initiating frame exists, and is the same as the
+	       current frame.  We stop, because the exception has been
+	       caught.
+
+	       3. The initiating frame exists and is different from
+	       the current frame.  This means the exception has been
+	       caught beneath the initiating frame, so keep going.  */
+	    struct frame_info *init_frame
+	      = frame_find_by_id (ecs->event_thread->initiating_frame);
+
+	    gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
+			!= NULL);
+	    delete_exception_resume_breakpoint (ecs->event_thread);
+
+	    if (init_frame)
+	      {
+		struct frame_id current_id
+		  = get_frame_id (get_current_frame ());
+		if (frame_id_eq (current_id,
+				 ecs->event_thread->initiating_frame))
+		  {
+		    /* Case 2.  Fall through.  */
+		  }
+		else
+		  {
+		    /* Case 3.  */
+		    keep_going (ecs);
+		    return;
+		  }
+	      }
+
+	    /* For Cases 1 and 2, remove the step-resume breakpoint,
+	       if it exists.  */
+	    delete_step_resume_breakpoint (ecs->event_thread);
+	  }
 
 	ecs->event_thread->control.stop_step = 1;
 	print_end_stepping_range_reason ();
@@ -5109,6 +5180,97 @@ insert_longjmp_resume_breakpoint (struct gdbarch *gdbarch, CORE_ADDR pc)
     set_momentary_breakpoint_at_pc (gdbarch, pc, bp_longjmp_resume);
 }
 
+/* Insert an exception resume breakpoint.  TP is the thread throwing
+   the exception.  The block B is the block of the unwinder debug hook
+   function.  FRAME is the frame corresponding to the call to this
+   function.  SYM is the symbol of the function argument holding the
+   target PC of the exception.  */
+
+static void
+insert_exception_resume_breakpoint (struct thread_info *tp,
+				    struct block *b,
+				    struct frame_info *frame,
+				    struct symbol *sym)
+{
+  struct gdb_exception e;
+
+  /* We want to ignore errors here.  */
+  TRY_CATCH (e, RETURN_MASK_ERROR)
+    {
+      struct symbol *vsym;
+      struct value *value;
+      CORE_ADDR handler;
+      struct breakpoint *bp;
+
+      vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
+      value = read_var_value (vsym, frame);
+      /* If the value was optimized out, revert to the old behavior.  */
+      if (! value_optimized_out (value))
+	{
+	  handler = value_as_address (value);
+
+	  if (debug_infrun)
+	    fprintf_unfiltered (gdb_stdlog,
+				"infrun: exception resume at %lx\n",
+				(unsigned long) handler);
+
+	  bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
+					       handler, bp_exception_resume);
+	  bp->thread = tp->num;
+	  inferior_thread ()->control.exception_resume_breakpoint = bp;
+	}
+    }
+}
+
+/* This is called when an exception has been intercepted.  Check to
+   see whether the exception's destination is of interest, and if so,
+   set an exception resume breakpoint there.  */
+
+static void
+check_exception_resume (struct execution_control_state *ecs,
+			struct frame_info *frame, struct symbol *func)
+{
+  struct gdb_exception e;
+
+  TRY_CATCH (e, RETURN_MASK_ERROR)
+    {
+      struct block *b;
+      struct dict_iterator iter;
+      struct symbol *sym;
+      int argno = 0;
+
+      /* The exception breakpoint is a thread-specific breakpoint on
+	 the unwinder's debug hook, declared as:
+	 
+	 void _Unwind_DebugHook (void *cfa, void *handler);
+	 
+	 The CFA argument indicates the frame to which control is
+	 about to be transferred.  HANDLER is the destination PC.
+	 
+	 We ignore the CFA and set a temporary breakpoint at HANDLER.
+	 This is not extremely efficient but it avoids issues in gdb
+	 with computing the DWARF CFA, and it also works even in weird
+	 cases such as throwing an exception from inside a signal
+	 handler.  */
+
+      b = SYMBOL_BLOCK_VALUE (func);
+      ALL_BLOCK_SYMBOLS (b, iter, sym)
+	{
+	  if (!SYMBOL_IS_ARGUMENT (sym))
+	    continue;
+
+	  if (argno == 0)
+	    ++argno;
+	  else
+	    {
+	      insert_exception_resume_breakpoint (ecs->event_thread,
+						  b, frame, sym);
+	      break;
+	    }
+	}
+    }
+}
+
 static void
 stop_stepping (struct execution_control_state *ecs)
 {