unpack_sequence(): In finally clause, watch out for Py_DECREF

evaluating its arguments twice.

diff --git a/Python/ceval.c b/Python/ceval.c
index e08e1c972fb068fa695016b209cb9f67a606e389..c920d30a3a03a82910d261c3752a216c73fa3b3b 100644 (file)
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -2076,8 +2076,8 @@ unpack_sequence(v, argcnt, sp)
                                "unpack sequence of wrong size");
        /* fall through */
 finally:
-       for (; i > 0; i--)
-               Py_DECREF(*sp++);
+       for (; i > 0; i--, sp++)
+               Py_DECREF(*sp);
 
        return 0;
 }