Index: ChangeLog
===================================================================
RCS file: /cvs/src/src/gdb/ChangeLog,v
retrieving revision 1.14894
diff -u -r1.14894 ChangeLog
--- ChangeLog	9 Dec 2012 18:39:57 -0000	1.14894
+++ ChangeLog	11 Dec 2012 15:26:11 -0000
@@ -1,3 +1,9 @@
+2012-12-10  Ali Anwar  <ali_anwar@codesourcery.com>
+
+	PR threads/13217
+	* thread.c (thread_apply_all_command): Check for valid threads 
+	and thread count.
+
 2012-12-09  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
 	* configure.ac (CC_HAS_LONG_LONG): Replace by AC_MSG_ERROR.
Index: thread.c
===================================================================
RCS file: /cvs/src/src/gdb/thread.c,v
retrieving revision 1.149
diff -u -r1.149 thread.c
--- thread.c	27 Jul 2012 00:52:36 -0000	1.149
+++ thread.c	11 Dec 2012 15:31:52 -0000
@@ -1178,7 +1178,6 @@
 static void
 thread_apply_all_command (char *cmd, int from_tty)
 {
-  struct thread_info *tp;
   struct cleanup *old_chain;
   char *saved_cmd;
 
@@ -1193,18 +1192,32 @@
      execute_command.  */
   saved_cmd = xstrdup (cmd);
   make_cleanup (xfree, saved_cmd);
-  for (tp = thread_list; tp; tp = tp->next)
-    if (thread_alive (tp))
-      {
-	switch_to_thread (tp->ptid);
-
-	printf_filtered (_("\nThread %d (%s):\n"),
-			 tp->num, target_pid_to_str (inferior_ptid));
-	execute_command (cmd, from_tty);
-	strcpy (cmd, saved_cmd);	/* Restore exact command used
-					   previously.  */
-      }
 
+  if (thread_count ())
+    {
+      struct thread_info *tp_array;
+      struct thread_info *tp;
+      int i, k;
+
+      /* Save a copy of the thread_list in case we execute detach
+         command.  */
+      tp_array =  xmalloc (sizeof (struct thread_info) * thread_count ());
+      for (i = 0, tp = thread_list; tp; i++, tp = tp->next)
+        tp_array[i] = *tp;
+
+      for (k = 0; k != i; k++)
+        if (thread_alive (&tp_array[k]))
+          {
+            switch_to_thread ((&tp_array[k])->ptid);
+
+            printf_filtered (_("\nThread %d (%s):\n"),
+                             (&tp_array[k])->num, target_pid_to_str (inferior_ptid));
+            execute_command (cmd, from_tty);
+            strcpy (cmd, saved_cmd);        /* Restore exact command used
+                                               previously.  */
+           }
+       xfree (tp_array);
+    }
   do_cleanups (old_chain);
 }
Index: testsuite/gdb.threads/threadapply.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.threads/threadapply.exp,v
retrieving revision 1.15
diff -u -r1.15 threadapply.exp
--- testsuite/gdb.threads/threadapply.exp	26 Jun 2012 19:23:20 -0000	1.15
+++ testsuite/gdb.threads/threadapply.exp	11 Dec 2012 15:26:20 -0000
@@ -63,3 +63,4 @@
 gdb_test "up" ".*in main.*" "go up in the stack frame" 
 gdb_test "thread apply all print 1"  "Thread ..*\\\$\[0-9]+ = 1.*Thread ..*\\\$\[0-9]+ = 1.*Thread ..*\\\$\[0-9]+ = 1.*Thread ..*\\\$\[0-9]+ = 1.*Thread ..*\\\$\[0-9]+ = 1.*Thread ..*\\\$\[0-9]+ = 1" "run a simple print command on all threads"
 gdb_test "down" "#0.*thread_function.*" "go down and check selected frame"
+gdb_test "thread apply all detach" "Detaching from.*" "detach all threads"