2011-10-28 Pedro Alves <pedro@codesourcery.com>

	gdb/
	* linux-nat.c (linux_nat_filter_event): Remove `options'
	parameter, and dead code that used it.  If we're handling a
	PTRACE_EVENT_EXEC event, and the thread group leader is no longer
	in our lwp list, re-add it.
	(check_zombie_leaders): New.
	(linux_nat_wait_1): Remove `options' and `pid' locals.  Always
	wait for children with WNOHANG, and always wait for all children.
	Don't check for no resumed children upfront.  Simplify wait loop.
	Check for zombie thread group leaders after handling all wait
	statuses.  Return TARGET_WAITKIND_NO_RESUMED if there no
	unwaited-for children left.
	* infrun.c (fetch_inferior_event): Handle TARGET_WAITKIND_NO_RESUMED.
	(handle_inferior_event): Handle TARGET_WAITKIND_NO_RESUMED.
	(normal_stop): Handle TARGET_WAITKIND_NO_RESUMED.
	* target.h (enum target_waitkind) <TARGET_WAITKIND_NO_RESUMED>: New.

	gdb/testsuite/
	* gdb.threads/no-unwaited-for-left.c: New.
	* gdb.threads/no-unwaited-for-left.exp: New.
	* gdb.threads/non-ldr-exc-1.c: New.
	* gdb.threads/non-ldr-exc-1.exp: New.
	* gdb.threads/non-ldr-exc-2.c: New.
	* gdb.threads/non-ldr-exc-2.exp: New.
	* gdb.threads/non-ldr-exc-3.c: New.
	* gdb.threads/non-ldr-exc-3.exp: New.
	* gdb.threads/non-ldr-exc-4.c: New.
	* gdb.threads/non-ldr-exc-4.exp: New.

11 files changed, 743 insertions, 0 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index f26044b..479676a 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,16 @@
+2011-10-28  Pedro Alves  <pedro@codesourcery.com>
+
+	* gdb.threads/no-unwaited-for-left.c: New.
+	* gdb.threads/no-unwaited-for-left.exp: New.
+	* gdb.threads/non-ldr-exc-1.c: New.
+	* gdb.threads/non-ldr-exc-1.exp: New.
+	* gdb.threads/non-ldr-exc-2.c: New.
+	* gdb.threads/non-ldr-exc-2.exp: New.
+	* gdb.threads/non-ldr-exc-3.c: New.
+	* gdb.threads/non-ldr-exc-3.exp: New.
+	* gdb.threads/non-ldr-exc-4.c: New.
+	* gdb.threads/non-ldr-exc-4.exp: New.
+
 2011-10-28  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
 	* gdb.base/async-shell.exp: Skip the testfile for use_gdb_stub.
diff --git a/gdb/testsuite/gdb.threads/no-unwaited-for-left.c b/gdb/testsuite/gdb.threads/no-unwaited-for-left.c
new file mode 100644
index 0000000..d8c32cf
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/no-unwaited-for-left.c
@@ -0,0 +1,68 @@
+/* Copyright 2007, 2011 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <assert.h>
+#include <unistd.h>
+
+static volatile pthread_t main_thread;
+pthread_barrier_t barrier;
+
+static void *
+thread_a (void *arg)
+{
+  int i;
+
+  return 0; /* break-here */
+}
+
+static void *
+thread_b (void *arg)
+{
+  int i;
+
+  pthread_barrier_wait (&barrier);
+
+  i = pthread_join (main_thread, NULL);
+  assert (i == 0);
+
+  return arg;
+}
+
+int
+main (void)
+{
+  pthread_t thread;
+  int i;
+
+  /* First test resuming only `thread_a', which exits.  */
+  i = pthread_create (&thread, NULL, thread_a, NULL);
+  assert (i == 0);
+  pthread_join (thread, NULL);
+
+  /* Then test resuming only the leader, which also exits.  */
+  main_thread = pthread_self ();
+
+  pthread_barrier_init (&barrier, NULL, 2);
+
+  i = pthread_create (&thread, NULL, thread_b, NULL);
+  assert (i == 0);
+
+  pthread_barrier_wait (&barrier);
+
+  pthread_exit (NULL); /* break-here-2 */
+  /* NOTREACHED */
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/no-unwaited-for-left.exp b/gdb/testsuite/gdb.threads/no-unwaited-for-left.exp
new file mode 100644
index 0000000..ed991de
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/no-unwaited-for-left.exp
@@ -0,0 +1,69 @@
+# Copyright (C) 2007, 2011 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Exit of a thread when there are other threads in the inferior should
+# not hang GDB.
+
+set testfile "no-unwaited-for-left"
+set srcfile ${testfile}.c
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    return -1
+}
+
+clean_restart ${executable}
+
+if ![runto_main] {
+    return -1
+}
+
+gdb_breakpoint $srcfile:[gdb_get_line_number "break-here"]
+gdb_continue_to_breakpoint "break-here" ".* break-here .*"
+
+# Resume only the second thread
+gdb_test_no_output "set scheduler-locking on" \
+    "enable scheduler-locking, for thread 2"
+
+# Continue.  Thread 2 exits, and the main thread was already stopped.
+gdb_test "continue" \
+    "No unwaited-for children left." \
+    "continue stops when thread 2 exits"
+
+gdb_test "info threads" \
+	 "\r\n\[ \t\]*Id\[ \t\]+Target\[ \t\]+Id\[ \t\]+Frame\[ \t\]*\r\n *1 *Thread \[^\r\n\]* \[^\r\n\]*.*The current thread <Thread ID 2> has terminated.*" \
+	 "only main thread left, thread 2 terminated"
+
+# Select the main thread, let the third thread start, and stop at the
+# main thread breakpoint.
+gdb_test "thread 1" "" "select main thread"
+gdb_test_no_output "set scheduler-locking off" \
+    "disable scheduler-locking, letting new thread start"
+
+gdb_breakpoint [gdb_get_line_number "break-here-2"]
+gdb_continue_to_breakpoint "break-here-2" ".* break-here-2 .*"
+
+# Let the main thread continue alone.
+gdb_test_no_output "set scheduler-locking on" \
+    "enable scheduler-locking, for main thread"
+# The main thread exits, and thread 3 was already stopped.
+gdb_test "continue" \
+    "No unwaited-for children left." \
+    "continue stops when the main thread exits"
+
+gdb_test "info threads" \
+	 "\r\n\[ \t\]*Id\[ \t\]+Target\[ \t\]+Id\[ \t\]+Frame\[ \t\]*\r\n *3 *Thread \[^\r\n\]* \[^\r\n\]*.*The current thread <Thread ID 1> has terminated.*" \
+	 "only thread 3 left, main thread terminated"
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-1.c b/gdb/testsuite/gdb.threads/non-ldr-exc-1.c
new file mode 100644
index 0000000..04b98e9
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-1.c
@@ -0,0 +1,61 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <assert.h>
+
+static const char *image;
+static char *argv1 = "go away";
+
+static void *
+thread_execler (void *arg)
+{
+  /* Exec ourselves again.  */
+  if (execl (image, image, argv1, NULL) == -1) /* break-here */
+    {
+      perror ("execl");
+      abort ();
+    }
+
+  return NULL;
+}
+
+int
+main (int argc, char **argv)
+{
+  pthread_t thread;
+  int i;
+
+  image = argv[0];
+
+  /* Pass "inf" as argument to keep re-execing ad infinitum, which can
+     be useful for manual testing.  Passing any other argument exits
+     immediately (and that's what the execl above does by
+     default).  */
+  if (argc == 2 && strcmp (argv[1], "inf") == 0)
+    argv1 = argv[1];
+  else if (argc > 1)
+    exit (0);
+
+  i = pthread_create (&thread, NULL, thread_execler, NULL);
+  assert (i == 0);
+  pthread_join (thread, NULL);
+
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-1.exp b/gdb/testsuite/gdb.threads/non-ldr-exc-1.exp
new file mode 100644
index 0000000..edfda33
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-1.exp
@@ -0,0 +1,65 @@
+# Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test that when a thread other than the main thread execs, we follow
+# through to the new incarnation of the main thread.
+
+# No exec event support in the remote protocol.
+if { [is_remote target] } then {
+    continue
+}
+
+set testfile "non-ldr-exc-1"
+set srcfile ${testfile}.c
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    return -1
+}
+
+proc do_test { lock_sched } {
+    global pf_prefix
+    global executable
+
+    set save_pf_prefix $pf_prefix
+    lappend pf_prefix "lock-sched$lock_sched:"
+
+    clean_restart ${executable}
+
+    if ![runto_main] {
+	set pf_prefix $save_pf_prefix
+	return -1
+    }
+
+    gdb_breakpoint [gdb_get_line_number "break-here"]
+    gdb_continue_to_breakpoint "break-here" ".* break-here .*"
+
+    # Also test with sched-lock to make sure we can follow the
+    # non-leader thread execing even though the main thread wasn't
+    # resumed before the exec.
+    if { $lock_sched } {
+	gdb_test_no_output "set scheduler-locking on"
+    }
+
+    gdb_test "continue" \
+	".*is executing new program.*Breakpoint 1, main.* at .*" \
+	"continue over exec"
+
+    set pf_prefix $save_pf_prefix
+}
+
+do_test 0
+do_test 1
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-2.c b/gdb/testsuite/gdb.threads/non-ldr-exc-2.c
new file mode 100644
index 0000000..69a21d4
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-2.c
@@ -0,0 +1,70 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <assert.h>
+
+static const char *image;
+static volatile pthread_t main_thread;
+static char *argv1 = "go away";
+
+static void *
+thread_execler (void *arg)
+{
+  int i;
+
+  i = pthread_join (main_thread, NULL);
+  assert (i == 0);
+
+  /* Exec ourselves again.  */
+  if (execl (image, image, argv1, NULL) == -1) /* break-here */
+    {
+      perror ("execl");
+      abort ();
+    }
+
+  return NULL;
+}
+
+int
+main (int argc, char **argv)
+{
+  pthread_t thread;
+  int i;
+
+  image = argv[0];
+
+  /* Pass "inf" as argument to keep re-execing ad infinitum, which can
+     be useful for manual testing.  Passing any other argument exits
+     immediately (and that's what the execl above does by
+     default).  */
+  if (argc == 2 && strcmp (argv[1], "inf") == 0)
+    argv1 = argv[1];
+  else if (argc > 1)
+    exit (0);
+
+  main_thread = pthread_self ();
+
+  i = pthread_create (&thread, NULL, thread_execler, NULL);
+  assert (i == 0);
+
+  pthread_exit (NULL);
+  /* NOTREACHED */
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-2.exp b/gdb/testsuite/gdb.threads/non-ldr-exc-2.exp
new file mode 100644
index 0000000..0686516
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-2.exp
@@ -0,0 +1,70 @@
+# Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test that when a thread other than the main thread execs, we follow
+# through to the new incarnation of the main thread, even if the main
+# thread had already exited before the exec.
+
+# No exec event support in the remote protocol.
+if { [is_remote target] } then {
+    continue
+}
+
+set testfile "non-ldr-exc-2"
+set srcfile ${testfile}.c
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    return -1
+}
+
+proc do_test { lock_sched } {
+    global pf_prefix
+    global executable
+
+    set save_pf_prefix $pf_prefix
+    lappend pf_prefix "lock-sched$lock_sched:"
+
+    clean_restart ${executable}
+
+    if ![runto_main] {
+	set pf_prefix $save_pf_prefix
+	return -1
+    }
+
+    gdb_breakpoint [gdb_get_line_number "break-here"]
+    gdb_continue_to_breakpoint "break-here" ".* break-here .*"
+
+    gdb_test "info threads" \
+	 "\r\n\[ \t\]*Id\[ \t\]+Target\[ \t\]+Id\[ \t\]+Frame\[ \t\]*\r\n\\* 2 *Thread \[^\r\n\]* at \[^\r\n\]*" \
+	 "single thread left"
+
+    # Also test with sched-lock to make sure we can follow the
+    # non-leader thread execing even though the main thread wasn't
+    # resumed before the exec.
+    if { $lock_sched } {
+	gdb_test_no_output "set scheduler-locking on"
+    }
+
+    gdb_test "continue" \
+	".*is executing new program.*Breakpoint 1, main.* at .*" \
+	"continue over exec"
+
+    set pf_prefix $save_pf_prefix
+}
+
+do_test 0
+do_test 1
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-3.c b/gdb/testsuite/gdb.threads/non-ldr-exc-3.c
new file mode 100644
index 0000000..64597e4
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-3.c
@@ -0,0 +1,100 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <assert.h>
+
+static const char *image;
+static volatile pthread_t main_thread;
+static pthread_barrier_t barrier;
+static char *argv1 = "go away";
+
+static void *
+thread_execler (void *arg)
+{
+  int i;
+
+  pthread_barrier_wait (&barrier);
+
+  i = pthread_join (main_thread, NULL);
+  assert (i == 0);
+
+  /* Exec ourselves again.  */
+  if (execl (image, image, argv1, NULL) == -1) /* break-here */
+    {
+      perror ("execl");
+      abort ();
+    }
+
+  return NULL;
+}
+
+static void *
+just_loop (void *arg)
+{
+  unsigned int i;
+
+  pthread_barrier_wait (&barrier);
+
+  for (i = 1; i > 0; i++)
+    usleep (1);
+
+  return NULL;
+}
+
+#define THREADS 5
+
+pthread_t loop_thread[THREADS];
+
+int
+main (int argc, char **argv)
+{
+  pthread_t thread;
+  int i, t;
+
+  image = argv[0];
+
+  /* Pass "inf" as argument to keep re-execing ad infinitum, which can
+     be useful for manual testing.  Passing any other argument exits
+     immediately (and that's what the execl above does by
+     default).  */
+  if (argc == 2 && strcmp (argv[1], "inf") == 0)
+    argv1 = argv[1];
+  else if (argc > 1)
+    exit (0);
+
+  main_thread = pthread_self ();
+
+  pthread_barrier_init (&barrier, NULL, 2 + THREADS);
+
+  i = pthread_create (&thread, NULL, thread_execler, NULL);
+  assert (i == 0);
+
+  for (t = 0; t < THREADS; t++)
+    {
+      i = pthread_create (&loop_thread[t], NULL, just_loop, NULL);
+      assert (i == 0);
+    }
+
+  pthread_barrier_wait (&barrier);
+
+  pthread_exit (NULL);
+  /* NOTREACHED */
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-3.exp b/gdb/testsuite/gdb.threads/non-ldr-exc-3.exp
new file mode 100644
index 0000000..8eaafcf
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-3.exp
@@ -0,0 +1,68 @@
+# Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test that when a thread other than the main thread execs, we follow
+# through to the new incarnation of the main thread, even if the main
+# thread had already exited before the exec.  This differs from
+# non-ldr-exc-2.exp in that we have more than two threads in the
+# program when the exec happens.
+
+# No exec event support in the remote protocol.
+if { [is_remote target] } then {
+    continue
+}
+
+set testfile "non-ldr-exc-3"
+set srcfile ${testfile}.c
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    return -1
+}
+
+proc do_test { lock_sched } {
+    global pf_prefix
+    global executable
+
+    set save_pf_prefix $pf_prefix
+    lappend pf_prefix "lock-sched$lock_sched:"
+
+    clean_restart ${executable}
+
+    if ![runto_main] {
+	set pf_prefix $save_pf_prefix
+	return -1
+    }
+
+    gdb_breakpoint [gdb_get_line_number "break-here"]
+    gdb_continue_to_breakpoint "break-here" ".* break-here .*"
+
+    # Also test with sched-lock to make sure we can follow the
+    # non-leader thread execing even though the main thread wasn't
+    # resumed before the exec.
+    if { $lock_sched } {
+	gdb_test_no_output "set scheduler-locking on"
+    }
+
+    gdb_test "continue" \
+	".*is executing new program.*Breakpoint 1, main.* at .*" \
+	"continue over exec"
+
+    set pf_prefix $save_pf_prefix
+}
+
+do_test 0
+do_test 1
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-4.c b/gdb/testsuite/gdb.threads/non-ldr-exc-4.c
new file mode 100644
index 0000000..57dea04
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-4.c
@@ -0,0 +1,92 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <assert.h>
+
+static const char *image;
+static pthread_barrier_t barrier;
+static char *argv1 = "go away";
+
+static void *
+thread_execler (void *arg)
+{
+  int i;
+
+  pthread_barrier_wait (&barrier);
+
+  /* Exec ourselves again.  */
+  if (execl (image, image, argv1, NULL) == -1) /* break-here */
+    {
+      perror ("execl");
+      abort ();
+    }
+
+  return NULL;
+}
+
+static void *
+just_loop (void *arg)
+{
+  unsigned int i;
+
+  pthread_barrier_wait (&barrier);
+
+  for (i = 1; i > 0; i++)
+    usleep (1);
+
+  return NULL;
+}
+
+#define THREADS 5
+
+pthread_t loop_thread[THREADS];
+
+int
+main (int argc, char **argv)
+{
+  pthread_t thread;
+  int i, t;
+
+  image = argv[0];
+
+  /* Pass "inf" as argument to keep re-execing ad infinitum, which can
+     be useful for manual testing.  Passing any other argument exits
+     immediately (and that's what the execl above does by
+     default).  */
+  if (argc == 2 && strcmp (argv[1], "inf") == 0)
+    argv1 = argv[1];
+  else if (argc > 1)
+    exit (0);
+
+  pthread_barrier_init (&barrier, NULL, 2 + THREADS);
+
+  i = pthread_create (&thread, NULL, thread_execler, NULL);
+  assert (i == 0);
+
+  for (t = 0; t < THREADS; t++)
+    {
+      i = pthread_create (&loop_thread[t], NULL, just_loop, NULL);
+      assert (i == 0);
+    }
+
+  pthread_barrier_wait (&barrier);
+  pthread_join (thread, NULL);
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/non-ldr-exc-4.exp b/gdb/testsuite/gdb.threads/non-ldr-exc-4.exp
new file mode 100644
index 0000000..3ca099b
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/non-ldr-exc-4.exp
@@ -0,0 +1,67 @@
+# Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test that when a thread other than the main thread execs, we follow
+# through to the new incarnation of the main thread.  This differs
+# from non-ldr-exc-1.exp in that we have more than two threads in the
+# program when the exec happens.
+
+# No exec event support in the remote protocol.
+if { [is_remote target] } then {
+    continue
+}
+
+set testfile "non-ldr-exc-4"
+set srcfile ${testfile}.c
+set executable ${testfile}
+set binfile ${objdir}/${subdir}/${executable}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    return -1
+}
+
+proc do_test { lock_sched } {
+    global pf_prefix
+    global executable
+
+    set save_pf_prefix $pf_prefix
+    lappend pf_prefix "lock-sched$lock_sched:"
+
+    clean_restart ${executable}
+
+    if ![runto_main] {
+	set pf_prefix $save_pf_prefix
+	return -1
+    }
+
+    gdb_breakpoint [gdb_get_line_number "break-here"]
+    gdb_continue_to_breakpoint "break-here" ".* break-here .*"
+
+    # Also test with sched-lock to make sure we can follow the
+    # non-leader thread execing even though the main thread wasn't
+    # resumed before the exec.
+    if { $lock_sched } {
+	gdb_test_no_output "set scheduler-locking on"
+    }
+
+    gdb_test "continue" \
+	".*is executing new program.*Breakpoint 1, main.* at .*" \
+	"continue over exec"
+
+    set pf_prefix $save_pf_prefix
+}
+
+do_test 0
+do_test 1