diff --git a/Python/ceval.c b/Python/ceval.c
index 97a734c..a93ceea 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -554,8 +554,16 @@
 /* Local variable macros */
 
 #define GETLOCAL(i)	(fastlocals[i])
-#define SETLOCAL(i, value)	do { Py_XDECREF(GETLOCAL(i)); \
-				     GETLOCAL(i) = value; } while (0)
+
+/* The SETLOCAL() macro must not DECREF the local variable in-place and
+   then store the new value; it must copy the old value to a temporary
+   value, then store the new value, and then DECREF the temporary value.
+   This is because it is possible that during the DECREF the frame is
+   accessed by other code (e.g. a __del__ method or gc.collect()) and the
+   variable would be pointing to already-freed memory. */
+#define SETLOCAL(i, value)	do { PyObject *tmp = GETLOCAL(i); \
+				     GETLOCAL(i) = value; \
+                                     Py_XDECREF(tmp); } while (0)
 
 /* Start of code */