Fix potential double-decref.

ZeroIntensity · ZeroIntensity · commit 63892dce4208 · 2025-08-03T14:07:02.000-04:00
diff --git a/Python/errors.c b/Python/errors.c
@@ -1499,10 +1499,11 @@ write_unraisable_exc_file(PyThreadState *tstate, PyObject *exc_type,
             // Nothing else to do
             return 0;
         }
+    } else {
+        Py_XDECREF(print_exception_fn);
     }
     // traceback module failed, fall back to pure C
     _PyErr_Clear(tstate);
-    Py_XDECREF(print_exception_fn);
 
     if (exc_tb != NULL && exc_tb != Py_None) {
         if (PyTraceBack_Print(exc_tb, file) < 0) {

Original file line number	Diff line number	Diff line change
`@@ -1499,10 +1499,11 @@ write_unraisable_exc_file(PyThreadState tstate, PyObject exc_type,`
`1499`	`1499`	`// Nothing else to do`
`1500`	`1500`	`return 0;`
`1501`	`1501`	`}`
	`1502`	`+ } else {`
	`1503`	`+ Py_XDECREF(print_exception_fn);`
`1502`	`1504`	`}`
`1503`	`1505`	`// traceback module failed, fall back to pure C`
`1504`	`1506`	`_PyErr_Clear(tstate);`
`1505`		`- Py_XDECREF(print_exception_fn);`
`1506`	`1507`
`1507`	`1508`	`if (exc_tb != NULL && exc_tb != Py_None) {`
`1508`	`1509`	`if (PyTraceBack_Print(exc_tb, file) < 0) {`