Hye-Shik Chang's fix for Bug 875692.

Improve signal handling, especially when using threads, by forcing an early
re-execution of PyEval_EvalFrame() "periodic" code when things_to_do is not
cleared by Py_MakePendingCalls().

M Misc/NEWS
M Python/ceval.c

Misc/NEWS

@@ -4,6 +4,19 @@ Python News
 
 (editors: check NEWS.help for information about editing NEWS using ReST.)
 
+What's New in Python 2.4 release candidate 2
+=====================================================
+
+*Release date: XX-NOV-2004*
+
+Core and builtins
+-----------------
+
+- Bug 875692: Improve signal handling, especially when using threads, by
+  forcing an early re-execution of PyEval_EvalFrame() "periodic" code when
+  things_to_do is not cleared by Py_MakePendingCalls().
+
+
 What's New in Python 2.4 (release candidate 1|beta 3)
 =====================================================
 

Python/ceval.c

@@ -786,6 +786,12 @@ PyEval_EvalFrame(PyFrameObject *f)
 					why = WHY_EXCEPTION;
 					goto on_error;
 				}
+				if (things_to_do)
+					/* MakePendingCalls() didn't succeed.
+					   Force early re-execution of this
+					   "periodic" code, possibly after
+					   a thread switch */
+					_Py_Ticker = 0;
 			}
 #ifdef WITH_THREAD
 			if (interpreter_lock) {