Regression with default scheduler-locking=step [Re: [pushed] Consecutive step-overs trigger internal error.]

diff --git a/gdb/btrace.c b/gdb/btrace.c
index 601eb41..87a171e 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -958,7 +958,7 @@  btrace_free_objfile (struct objfile *objfile)
 
   DEBUG ("free objfile");
 
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     btrace_clear (tp);
 }
 
diff --git a/gdb/gdbthread.h b/gdb/gdbthread.h
index 9f5dee6..64e37c3 100644
--- a/gdb/gdbthread.h
+++ b/gdb/gdbthread.h
@@ -317,10 +317,12 @@  void thread_change_ptid (ptid_t old_ptid, ptid_t new_ptid);
 typedef int (*thread_callback_func) (struct thread_info *, void *);
 extern struct thread_info *iterate_over_threads (thread_callback_func, void *);
 
-/* Traverse all threads.  */
+/* Traverse all threads, except those that have THREAD_EXITED
+   state.  */
 
-#define ALL_THREADS(T)				\
-  for (T = thread_list; T; T = T->next)
+#define ALL_NON_EXITED_THREADS(T)				\
+  for (T = thread_list; T; T = T->next) \
+    if ((T)->state != THREAD_EXITED)
 
 extern int thread_count (void);
 
diff --git a/gdb/infrun.c b/gdb/infrun.c
index 4e808d9..e8e26e0 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -2160,7 +2160,7 @@  find_thread_needs_step_over (int step, struct thread_info *except)
       return NULL;
     }
 
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     {
       /* Ignore the EXCEPT thread.  */
       if (tp == except)
@@ -5204,7 +5204,7 @@  switch_back_to_stepped_thread (struct execution_control_state *ecs)
 	 step/next/etc.  */
       stepping_thread = NULL;
       step_over = NULL;
-      ALL_THREADS (tp)
+      ALL_NON_EXITED_THREADS (tp)
         {
 	  /* Ignore threads of processes we're not resuming.  */
 	  if (!sched_multi
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index e0c537a8..6a9bfe1 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -206,7 +206,7 @@  record_btrace_open (char *args, int from_tty)
   gdb_assert (record_btrace_thread_observer == NULL);
 
   disable_chain = make_cleanup (null_cleanup, NULL);
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     if (args == NULL || *args == 0 || number_is_in_list (args, tp->num))
       {
 	btrace_enable (tp);
@@ -238,7 +238,7 @@  record_btrace_stop_recording (struct target_ops *self)
 
   record_btrace_auto_disable ();
 
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     if (tp->btrace.target != NULL)
       btrace_disable (tp);
 }
@@ -259,7 +259,7 @@  record_btrace_close (struct target_ops *self)
 
   /* We should have already stopped recording.
      Tear down btrace in case we have not.  */
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     btrace_teardown (tp);
 }
 
@@ -835,7 +835,7 @@  record_btrace_is_replaying (struct target_ops *self)
 {
   struct thread_info *tp;
 
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     if (btrace_is_replaying (tp))
       return 1;
 
@@ -1522,7 +1522,7 @@  record_btrace_resume (struct target_ops *ops, ptid_t ptid, int step,
 
   /* Stop replaying other threads if the thread to resume is not replaying.  */
   if (!btrace_is_replaying (tp) && execution_direction != EXEC_REVERSE)
-    ALL_THREADS (other)
+    ALL_NON_EXITED_THREADS (other)
       record_btrace_stop_replaying (other);
 
   /* As long as we're not replaying, just forward the request.  */
@@ -1572,7 +1572,7 @@  record_btrace_find_thread_to_move (ptid_t ptid)
     return tp;
 
   /* Otherwise, find one other thread that has been resumed.  */
-  ALL_THREADS (tp)
+  ALL_NON_EXITED_THREADS (tp)
     if ((tp->btrace.flags & BTHR_MOVE) != 0)
       return tp;
 
@@ -1777,7 +1777,7 @@  record_btrace_wait (struct target_ops *ops, ptid_t ptid,
 
   /* Stop all other threads. */
   if (!non_stop)
-    ALL_THREADS (other)
+    ALL_NON_EXITED_THREADS (other)
       other->btrace.flags &= ~BTHR_MOVE;
 
   /* Start record histories anew from the current position.  */
diff --git a/gdb/remote.c b/gdb/remote.c
index 6915dd8..b5318f1 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -4626,7 +4626,7 @@  append_pending_thread_resumptions (char *p, char *endp, ptid_t ptid)
 {
   struct thread_info *thread;
 
-  ALL_THREADS (thread)
+  ALL_NON_EXITED_THREADS (thread)
     if (ptid_match (thread->ptid, ptid)
 	&& !ptid_equal (inferior_ptid, thread->ptid)
 	&& thread->suspend.stop_signal != GDB_SIGNAL_0
diff --git a/gdb/testsuite/gdb.threads/thread-execl.exp b/gdb/testsuite/gdb.threads/thread-execl.exp
index d837fe4..14b96d2 100644
--- a/gdb/testsuite/gdb.threads/thread-execl.exp
+++ b/gdb/testsuite/gdb.threads/thread-execl.exp
@@ -28,19 +28,33 @@  if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
     return -1
 }
 
-clean_restart ${binfile}
-
-runto_main
-
-# Get ourselves to the thread that execs
-gdb_breakpoint "thread_execler"
-gdb_test "continue" ".*thread_execler.*" "continue to thread start"
-
-# Now set a breakpoint at `main', and step over the execl call.  The
-# breakpoint at main should be reached.  GDB should not try to revert
-# back to the old thread from the old image and resume stepping it
-# (since it is gone).
-gdb_breakpoint "main"
-gdb_test "next" ".*main.*" "get to main in new image"
+# Run the test proper.  SCHEDLOCK specifies what scheduler-locking
+# should be set to.
+
+proc do_test { schedlock } {
+    global binfile
+
+    with_test_prefix "schedlock $schedlock" {
+	clean_restart ${binfile}
+
+	if ![runto_main] {
+	    return 0
+	}
+
+	# Get ourselves to the thread that execs.
+	gdb_breakpoint "thread_execler"
+	gdb_test "continue" ".*thread_execler.*" "continue to thread start"
+
+	# Now set a breakpoint at `main', and step over the execl call.  The
+	# breakpoint at main should be reached.  GDB should not try to revert
+	# back to the old thread from the old image and resume stepping it
+	# (since it is gone).
+	gdb_breakpoint "main"
+	gdb_test_no_output "set scheduler-locking $schedlock"
+	gdb_test "next" ".*main.*" "get to main in new image"
+    }
+}
 
-return 0
+foreach schedlock {"off" "step" "on"} {
+    do_test $schedlock
+}
diff --git a/gdb/thread.c b/gdb/thread.c
index 7bc5271..532149d 100644
--- a/gdb/thread.c
+++ b/gdb/thread.c
@@ -1243,7 +1243,7 @@  thread_apply_all_command (char *cmd, int from_tty)
       ta_cleanup.tp_array = tp_array;
       ta_cleanup.count = tc;
 
-      ALL_THREADS (tp)
+      ALL_NON_EXITED_THREADS (tp)
         {
           tp_array[i] = tp;
           tp->refcount++;