#1683 prevent forking from interfering in threading storage
This should prevent some test_multiprocessing failures
diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
index d07258a..e297240 100644
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -925,5 +925,6 @@
 	main_thread = PyThread_get_thread_ident();
 	main_pid = getpid();
 	_PyImport_ReInitLock();
+	PyThread_ReInitTLS();
 #endif
 }