Make PyTraceBack_Here use the current thread, not the

frame's thread state. Fixes #1579370.
Will backport.

Misc/NEWS

@@ -12,6 +12,9 @@ What's New in Python 2.6 alpha 1?
 Core and builtins
 -----------------
 
+- Bug #1579370: Make PyTraceBack_Here use the current thread, not the
+  frame's thread state.
+
 - patch #1630975: Fix crash when replacing sys.stdout in sitecustomize.py
 
 - Patch #1507247: tarfile.py: use current umask for intermediate

Python/traceback.c

@@ -113,7 +113,7 @@ newtracebackobject(PyTracebackObject *next, PyFrameObject *frame)
 int
 PyTraceBack_Here(PyFrameObject *frame)
 {
-	PyThreadState *tstate = frame->f_tstate;
+	PyThreadState *tstate = PyThreadState_GET();
 	PyTracebackObject *oldtb = (PyTracebackObject *) tstate->curexc_traceback;
 	PyTracebackObject *tb = newtracebackobject(oldtb, frame);
 	if (tb == NULL)