* thread-db.c (TID_MAY_BE_REUSED): Define.

	(find_new_threads_callback): Detect thread id reuse.

diff --git a/rda/unix/ChangeLog b/rda/unix/ChangeLog
index 330c895..e1f39b2 100644 (file)
--- a/rda/unix/ChangeLog
+++ b/rda/unix/ChangeLog
@@ -1,3 +1,8 @@
+2011-11-30  Kevin Buettner  <kevinb@redhat.com>
+
+       * thread-db.c (TID_MAY_BE_REUSED): Define.
+       (find_new_threads_callback): Detect thread id reuse.
+
 2010-10-14  Kevin Buettner  <kevinb@redhat.com>
 
        * lwp-pool.c (hash_find): Initialize `do_step' in the newly allocated

diff --git a/rda/unix/thread-db.c b/rda/unix/thread-db.c
index 535ea4c..569248d 100644 (file)
--- a/rda/unix/thread-db.c
+++ b/rda/unix/thread-db.c
@@ -49,6 +49,7 @@
 int thread_db_noisy = 0;
 
 #define ALWAYS_UPDATE_THREAD_LIST 0
+#define TID_MAY_BE_REUSED 1
 
 /*
  * A tiny local symbol table.
@@ -1426,11 +1427,25 @@ find_new_threads_callback (const td_thrhandle_t *thandle, void *data)
 
   /* Enter the thread into a local list
      (unless it is TD_THR_UNKNOWN, which means its defunct). */
-  if ((thread = thread_list_lookup_by_tid (ti.ti_tid)) == NULL)
+  if ((thread = thread_list_lookup_by_tid (ti.ti_tid)) == NULL
+#if TID_MAY_BE_REUSED
+      || thread->ti.ti_lid != ti.ti_lid
+#endif
+      )
     {
       if (ti.ti_state != TD_THR_UNKNOWN)
        {
-         thread = add_thread_to_list (&ti);
+         if (thread)
+           {
+             /* Thread is being reused.  What has happened here is that
+                one thread has died and another was created using the
+                same thread identifier.  */
+             if (thread_db_noisy)
+               fprintf (stderr, "(thread deletion / reuse: %s)\n", thread_debug_name (thread));
+             thread->ti = ti;
+           }
+         else
+           thread = add_thread_to_list (&ti);
 
          if (thread_db_noisy)
            fprintf (stderr, "(new thread %s)\n", thread_debug_name (thread));