Don't touch frame_info objects if frame cache was reinitialized

[deliverable/binutils-gdb.git] / gdb / frame.c

diff --git a/gdb/frame.c b/gdb/frame.c
index d74d1d5c7c5d57c1e455ad379415873fe25447c0..a3599e8af6968a85a6054a3a8907980a2e863c52 100644 (file)
--- a/gdb/frame.c
+++ b/gdb/frame.c
@@ -53,6 +53,17 @@
 
 static struct frame_info *sentinel_frame;
 
+/* Number of calls to reinit_frame_cache.  */
+static unsigned int frame_cache_generation = 0;
+
+/* See frame.h.  */
+
+unsigned int
+get_frame_cache_generation ()
+{
+  return frame_cache_generation;
+}
+
 /* The values behind the global "set backtrace ..." settings.  */
 set_backtrace_options user_set_backtrace_options;
 
@@ -1843,6 +1854,8 @@ reinit_frame_cache (void)
 {
   struct frame_info *fi;
 
+  ++frame_cache_generation;
+
   /* Tear down all frame caches.  */
   for (fi = sentinel_frame; fi != NULL; fi = fi->prev)
     {
@@ -1922,6 +1935,8 @@ get_prev_frame_if_no_cycle (struct frame_info *this_frame)
   if (prev_frame->level == 0)
     return prev_frame;
 
+  unsigned int entry_generation = get_frame_cache_generation ();
+
   try
     {
       compute_frame_id (prev_frame);
@@ -1944,8 +1959,11 @@ get_prev_frame_if_no_cycle (struct frame_info *this_frame)
     }
   catch (const gdb_exception &ex)
     {
-      prev_frame->next = NULL;
-      this_frame->prev = NULL;
+      if (get_frame_cache_generation () == entry_generation)
+       {
+         prev_frame->next = NULL;
+         this_frame->prev = NULL;
+       }
 
       throw;
     }
@@ -2913,19 +2931,6 @@ frame_prepare_for_sniffer (struct frame_info *frame,
 static struct cmd_list_element *set_backtrace_cmdlist;
 static struct cmd_list_element *show_backtrace_cmdlist;
 
-static void
-set_backtrace_cmd (const char *args, int from_tty)
-{
-  help_list (set_backtrace_cmdlist, "set backtrace ", all_commands,
-            gdb_stdout);
-}
-
-static void
-show_backtrace_cmd (const char *args, int from_tty)
-{
-  cmd_show_list (show_backtrace_cmdlist, from_tty, "");
-}
-
 /* Definition of the "set backtrace" settings that are exposed as
    "backtrace" command options.  */
 
@@ -2969,16 +2974,16 @@ _initialize_frame ()
 
   gdb::observers::target_changed.attach (frame_observer_target_changed);
 
-  add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, _("\
+  add_basic_prefix_cmd ("backtrace", class_maintenance, _("\
 Set backtrace specific variables.\n\
 Configure backtrace variables such as the backtrace limit"),
-                 &set_backtrace_cmdlist, "set backtrace ",
-                 0/*allow-unknown*/, &setlist);
-  add_prefix_cmd ("backtrace", class_maintenance, show_backtrace_cmd, _("\
+                       &set_backtrace_cmdlist, "set backtrace ",
+                       0/*allow-unknown*/, &setlist);
+  add_show_prefix_cmd ("backtrace", class_maintenance, _("\
 Show backtrace specific variables.\n\
 Show backtrace variables such as the backtrace limit."),
-                 &show_backtrace_cmdlist, "show backtrace ",
-                 0/*allow-unknown*/, &showlist);
+                      &show_backtrace_cmdlist, "show backtrace ",
+                      0/*allow-unknown*/, &showlist);
 
   add_setshow_uinteger_cmd ("limit", class_obscure,
                            &user_set_backtrace_options.backtrace_limit, _("\