diff -urp src.old/winsup/cygwin/thread.cc src/winsup/cygwin/thread.cc
--- src.old/winsup/cygwin/thread.cc	Wed Apr 24 10:14:14 2002
+++ src/winsup/cygwin/thread.cc	Wed Apr 24 10:24:01 2002
@@ -909,7 +909,7 @@ thread_init_wrapper (void *_arg)
   TlsSetValue (MT_INTERFACE->thread_self_dwTlsIndex, thread);
 
   // if thread is detached force cleanup on exit
-  if (thread->attr.joinable == PTHREAD_CREATE_DETACHED)
+  if (thread->attr.joinable == PTHREAD_CREATE_DETACHED && thread->joiner == NULL)
     thread->joiner = __pthread_self();
 
 #ifdef _CYG_THREAD_FAILSAFE
@@ -1535,8 +1535,8 @@ __pthread_join (pthread_t *thread, void 
 
   else
     {
-      (*thread)->attr.joinable = PTHREAD_CREATE_DETACHED;
       (*thread)->joiner = joiner;
+      (*thread)->attr.joinable = PTHREAD_CREATE_DETACHED;
       WaitForSingleObject ((*thread)->win32_obj_id, INFINITE);
       if (return_val)
          *return_val = (*thread)->return_ptr;
@@ -1560,9 +1560,9 @@ __pthread_detach (pthread_t *thread)
       return EINVAL;
     }
 
-  (*thread)->attr.joinable = PTHREAD_CREATE_DETACHED;
   // force cleanup on exit
   (*thread)->joiner = *thread;
+  (*thread)->attr.joinable = PTHREAD_CREATE_DETACHED;
 
   return 0;
 }