SF bug #483469: crash on unbounded recursion in __del__.
PyEval_EvalCodeEx(): increment tstate->recursion_depth around the
decref of the frame, because the C stack for this call is still in
use and the decref can lead to __del__ methods getting called.
While this gives tstate->recursion_depth a value proportional to the
depth of the C stack (instead of a small constant no matter how
deeply __del__s recurse), it's not enough to stop the reported crash
when using the default recursion limit on Windows.
Bugfix candidate.
diff --git a/Python/ceval.c b/Python/ceval.c
index 21ee3db..fd602b0 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -2560,7 +2560,15 @@
fail: /* Jump here from prelude on failure */
+ /* decref'ing the frame can cause __del__ methods to get invoked,
+ which can call back into Python. While we're done with the
+ current Python frame (f), the associated C stack is still in use,
+ so recursion_depth must be boosted for the duration.
+ */
+ assert(tstate != NULL);
+ ++tstate->recursion_depth;
Py_DECREF(f);
+ --tstate->recursion_depth;
return retval;
}