Use gdb::checked_static_cast for watchpoints

This replaces some casts to 'watchpoint *' with checked_static_cast.
In one spot, an unnecessary block is also removed.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

gdb/breakpoint.c

@@ -5243,13 +5243,12 @@ enum wp_check_result
 static wp_check_result
 watchpoint_check (bpstat *bs)
 {
-  struct watchpoint *b;
   frame_info_ptr fr;
   bool within_current_scope;
 
   /* BS is built from an existing struct breakpoint.  */
   gdb_assert (bs->breakpoint_at != NULL);
-  b = (struct watchpoint *) bs->breakpoint_at;
+  watchpoint *b = gdb::checked_static_cast<watchpoint *> (bs->breakpoint_at);
 
   /* If this is a local watchpoint, we only want to check if the
      watchpoint frame is in scope if the current thread is the thread
@@ -5405,15 +5404,12 @@ static void
 bpstat_check_watchpoint (bpstat *bs)
 {
   const struct bp_location *bl;
-  struct watchpoint *b;
 
   /* BS is built for existing struct breakpoint.  */
   bl = bs->bp_location_at.get ();
   gdb_assert (bl != NULL);
-  b = (struct watchpoint *) bs->breakpoint_at;
+  watchpoint *b = gdb::checked_static_cast<watchpoint *> (bs->breakpoint_at);
-  gdb_assert (b != NULL);
 
-    {
   bool must_check_value = false;
 
   if (b->type == bp_watchpoint)
@@ -5563,7 +5559,6 @@ bpstat_check_watchpoint (bpstat *bs)
       bs->stop = false;
     }
 }
-}
 
 /* For breakpoints that are currently marked as telling gdb to stop,
    check conditions (condition proper, frame, thread and ignore count)
@@ -5625,7 +5620,7 @@ bpstat_check_breakpoint_conditions (bpstat *bs, thread_info *thread)
 
   if (is_watchpoint (b))
     {
-      struct watchpoint *w = (struct watchpoint *) b;
+      watchpoint *w = gdb::checked_static_cast<watchpoint *> (b);
 
       cond = w->cond_exp.get ();
     }
@@ -5635,7 +5630,6 @@ bpstat_check_breakpoint_conditions (bpstat *bs, thread_info *thread)
   if (cond != nullptr && b->disposition != disp_del_at_next_stop)
     {
       bool within_current_scope = true;
-      struct watchpoint * w;
 
       /* We use scoped_value_mark because it could be a long time
 	 before we return to the command level and call
@@ -5643,10 +5637,9 @@ bpstat_check_breakpoint_conditions (bpstat *bs, thread_info *thread)
 	 might be in the middle of evaluating a function call.  */
       scoped_value_mark mark;
 
+      watchpoint *w = nullptr;
       if (is_watchpoint (b))
-	w = (struct watchpoint *) b;
+	w = gdb::checked_static_cast<watchpoint *> (b);
-      else
-	w = NULL;
 
       /* Need to select the frame, with all that implies so that
 	 the conditions will have the right context.  Because we
@@ -5794,7 +5787,8 @@ build_bpstat_chain (const address_space *aspace, CORE_ADDR bp_addr,
 	     iteration.  */
 	  if (b.type == bp_watchpoint_scope && b.related_breakpoint != &b)
 	    {
-	      struct watchpoint *w = (struct watchpoint *) b.related_breakpoint;
+	      watchpoint *w
+		= gdb::checked_static_cast<watchpoint *> (b.related_breakpoint);
 
 	      w->watchpoint_triggered = watch_triggered_yes;
 	    }
@@ -5918,7 +5912,8 @@ bpstat_stop_status (const address_space *aspace,
 	  && bs->breakpoint_at
 	  && is_hardware_watchpoint (bs->breakpoint_at))
 	{
-	  struct watchpoint *w = (struct watchpoint *) bs->breakpoint_at;
+	  watchpoint *w
+	    = gdb::checked_static_cast<watchpoint *> (bs->breakpoint_at);
 
 	  update_watchpoint (w, false /* don't reparse.  */);
 	  need_remove_insert = 1;
@@ -6568,7 +6563,7 @@ print_one_breakpoint_location (struct breakpoint *b,
     {
       if (is_watchpoint (b))
 	{
-	  struct watchpoint *w = (struct watchpoint *) b;
+	  watchpoint *w = gdb::checked_static_cast<watchpoint *> (b);
 
 	  /* Field 4, the address, is omitted (which makes the columns
 	     not line up too nicely with the headers, but the effect
@@ -6828,7 +6823,7 @@ print_one_breakpoint_location (struct breakpoint *b,
     {
       if (is_watchpoint (b))
 	{
-	  struct watchpoint *w = (struct watchpoint *) b;
+	  watchpoint *w = gdb::checked_static_cast<watchpoint *> (b);
 
 	  uiout->field_string ("original-location", w->exp_string.get ());
 	}
@@ -7257,8 +7252,8 @@ static bool
 watchpoint_locations_match (const struct bp_location *loc1,
 			    const struct bp_location *loc2)
 {
-  struct watchpoint *w1 = (struct watchpoint *) loc1->owner;
+  watchpoint *w1 = gdb::checked_static_cast<watchpoint *> (loc1->owner);
-  struct watchpoint *w2 = (struct watchpoint *) loc2->owner;
+  watchpoint *w2 = gdb::checked_static_cast<watchpoint *> (loc2->owner);
 
   /* Both of them must exist.  */
   gdb_assert (w1 != NULL);
@@ -12618,9 +12613,9 @@ delete_breakpoint (struct breakpoint *bpt)
       struct watchpoint *w;
 
       if (bpt->type == bp_watchpoint_scope)
-	w = (struct watchpoint *) bpt->related_breakpoint;
+	w = gdb::checked_static_cast<watchpoint *> (bpt->related_breakpoint);
       else if (bpt->related_breakpoint->type == bp_watchpoint_scope)
-	w = (struct watchpoint *) bpt;
+	w = gdb::checked_static_cast<watchpoint *> (bpt);
       else
 	w = NULL;
       if (w != NULL)
@@ -13784,7 +13779,7 @@ enable_breakpoint_disp (struct breakpoint *bpt, enum bpdisp disposition,
 
       try
 	{
-	  struct watchpoint *w = (struct watchpoint *) bpt;
+	  watchpoint *w = gdb::checked_static_cast<watchpoint *> (bpt);
 
 	  orig_enable_state = bpt->enable_state;
 	  bpt->enable_state = bp_enabled;

gdb/guile/scm-breakpoint.c

@@ -890,12 +890,11 @@ gdbscm_breakpoint_expression (SCM self)
 {
   breakpoint_smob *bp_smob
     = bpscm_get_valid_breakpoint_smob_arg_unsafe (self, SCM_ARG1, FUNC_NAME);
-  struct watchpoint *wp;
 
   if (!is_watchpoint (bp_smob->bp))
     return SCM_BOOL_F;
 
-  wp = (struct watchpoint *) bp_smob->bp;
+  watchpoint *wp = gdb::checked_static_cast<watchpoint *> (bp_smob->bp);
 
   const char *str = wp->exp_string.get ();
   if (! str)

gdb/python/py-breakpoint.c

@@ -549,14 +549,13 @@ bppy_get_expression (PyObject *self, void *closure)
 {
   const char *str;
   gdbpy_breakpoint_object *obj = (gdbpy_breakpoint_object *) self;
-  struct watchpoint *wp;
 
   BPPY_REQUIRE_VALID (obj);
 
   if (!is_watchpoint (obj->bp))
     Py_RETURN_NONE;
 
-  wp = (struct watchpoint *) obj->bp;
+  watchpoint *wp = gdb::checked_static_cast<watchpoint *> (obj->bp);
 
   str = wp->exp_string.get ();
   if (! str)