gdb/

	PR 11914
	* f-valprint.c (info_common_command): New variable frame_id.
	Reinitialize FI form FRAME_ID after each print_variable_and_value.
	* printcmd.c (print_variable_and_value): Extend function comment.
	Add comment for invalidated FRAME.
	* stack.c (backtrace_command_1): New variable frame_id.  Reinitialize
	FI form FRAME_ID after each print_frame_local_vars.
	(struct print_variable_and_value_data): Change frame to frame_id.
	(do_print_variable_and_value): New variable frame, initialize it from
	p->frame_id.  Add comment for invalidated FRAME.
	(print_frame_local_vars, print_frame_arg_vars): New function comment.
	Update CB_DATA.FRAME to CB_DATA.FRAME_ID initialization.  Add comment
	for invalidated FRAME.

gdb/testsuite/
	PR 11914
	* gdb.python/py-prettyprint.c (eval_func, eval_sub): New.
	(main): Call eval_sub.
	* gdb.python/py-prettyprint.exp:
	(python execfile ('py-prettyprint.py')): Move it earlier.
	New breakpoint for eval-break.
	(continue to breakpoint: eval-break, info locals): New test.
	(python execfile ('py-prettyprint.py')): Move it from here.
	* gdb.python/py-prettyprint.py (class pp_eval_type): New.
	(register_pretty_printers): Register pp_eval_type.

1 files changed, 46 insertions, 6 deletions

diff --git a/gdb/stack.c b/gdb/stack.c
index 2520e2c36db..35d379d55ec 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -1727,7 +1727,20 @@ backtrace_command_1 (char *count_exp, int show_locals, int from_tty)
          the frame->prev field gets set to NULL in that case).  */
       print_frame_info (fi, 1, LOCATION, 1);
       if (show_locals)
-	print_frame_local_vars (fi, 1, gdb_stdout);
+	{
+	  struct frame_id frame_id = get_frame_id (fi);
+
+	  print_frame_local_vars (fi, 1, gdb_stdout);
+
+	  /* print_frame_local_vars invalidates FI.  */
+	  fi = frame_find_by_id (frame_id);
+	  if (fi == NULL)
+	    {
+	      trailing = NULL;
+	      warning (_("Unable to restore previously selected frame."));
+	      break;
+	    }
+	}
 
       /* Save the last frame to check for error conditions.  */
       trailing = fi;
@@ -1919,7 +1932,7 @@ iterate_over_block_local_vars (struct block *block,
 
 struct print_variable_and_value_data
 {
-  struct frame_info *frame;
+  struct frame_id frame_id;
   int num_tabs;
   struct ui_file *stream;
   int values_printed;
@@ -1933,12 +1946,28 @@ do_print_variable_and_value (const char *print_name,
 			     void *cb_data)
 {
   struct print_variable_and_value_data *p = cb_data;
+  struct frame_info *frame;
+
+  frame = frame_find_by_id (p->frame_id);
+  if (frame == NULL)
+    {
+      warning (_("Unable to restore previously selected frame."));
+      return;
+    }
+
+  print_variable_and_value (print_name, sym, frame, p->stream, p->num_tabs);
+
+  /* print_variable_and_value invalidates FRAME.  */
+  frame = NULL;
 
-  print_variable_and_value (print_name, sym,
-			    p->frame, p->stream, p->num_tabs);
   p->values_printed = 1;
 }
 
+/* Print all variables from the innermost up to the function block of FRAME.
+   Print them with values to STREAM indented by NUM_TABS.
+
+   This function will invalidate FRAME.  */
+
 static void
 print_frame_local_vars (struct frame_info *frame, int num_tabs,
 			struct ui_file *stream)
@@ -1961,7 +1990,7 @@ print_frame_local_vars (struct frame_info *frame, int num_tabs,
       return;
     }
 
-  cb_data.frame = frame;
+  cb_data.frame_id = get_frame_id (frame);
   cb_data.num_tabs = 4 * num_tabs;
   cb_data.stream = stream;
   cb_data.values_printed = 0;
@@ -1970,6 +1999,9 @@ print_frame_local_vars (struct frame_info *frame, int num_tabs,
 				 do_print_variable_and_value,
 				 &cb_data);
 
+  /* do_print_variable_and_value invalidates FRAME.  */
+  frame = NULL;
+
   if (!cb_data.values_printed)
     fprintf_filtered (stream, _("No locals.\n"));
 }
@@ -2016,6 +2048,11 @@ iterate_over_block_arg_vars (struct block *b,
     }
 }
 
+/* Print all argument variables of the function of FRAME.
+   Print them with values to STREAM.
+
+   This function will invalidate FRAME.  */
+
 static void
 print_frame_arg_vars (struct frame_info *frame, struct ui_file *stream)
 {
@@ -2036,7 +2073,7 @@ print_frame_arg_vars (struct frame_info *frame, struct ui_file *stream)
       return;
     }
 
-  cb_data.frame = frame;
+  cb_data.frame_id = get_frame_id (frame);
   cb_data.num_tabs = 0;
   cb_data.stream = gdb_stdout;
   cb_data.values_printed = 0;
@@ -2044,6 +2081,9 @@ print_frame_arg_vars (struct frame_info *frame, struct ui_file *stream)
   iterate_over_block_arg_vars (SYMBOL_BLOCK_VALUE (func),
 			       do_print_variable_and_value, &cb_data);
 
+  /* do_print_variable_and_value invalidates FRAME.  */
+  frame = NULL;
+
   if (!cb_data.values_printed)
     fprintf_filtered (stream, _("No arguments.\n"));
 }