Merged revisions 64601 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r64601 | amaury.forgeotdarc | 2008-06-30 17:42:40 -0500 (Mon, 30 Jun 2008) | 11 lines

  #Issue3088 in-progress: Race condition with instances of classes derived from threading.local:

  When a thread touches such an object for the first time, a new thread-local __dict__ is created,
  and the __init__ method is run.
  But a thread switch can occur here; if the other thread touches the same object, it installs another
  __dict__; when the first thread resumes, it updates the dictionary of the second...

  This is the deep cause of the failures in test_multiprocessing involving "managers" objects.

  Also a 2.5 backport candidate.
........
diff --git a/Modules/_threadmodule.c b/Modules/_threadmodule.c
index 0fe9a76..d2299aa 100644
--- a/Modules/_threadmodule.c
+++ b/Modules/_threadmodule.c
@@ -293,7 +293,10 @@
 		}
 		
 	}
-	else if (self->dict != ldict) {
+
+	/* The call to tp_init above may have caused another thread to run.
+	   Install our ldict again. */
+	if (self->dict != ldict) {
 		Py_CLEAR(self->dict);
 		Py_INCREF(ldict);
 		self->dict = ldict;