diff -r b255ecb175c4 Python/import.c
--- a/Python/import.c	Mon Jul 07 23:07:27 2014 +0200
+++ b/Python/import.c	Mon Jul 07 23:09:22 2014 +0200
@@ -345,10 +345,49 @@ PyImport_Cleanup(void)
     PyObject *modules = interp->modules;
     PyObject *weaklist = NULL;
     char **p;
+    _Py_IDENTIFIER(__main__);
 
     if (modules == NULL)
         return; /* Already done */
 
+    /* We prepare a list which will receive (name, weakref) tuples of
+       modules when they are removed from sys.modules.  The name is used
+       for diagnosis messages (in verbose mode), while the weakref helps
+       detect those modules which have been held alive. */
+    weaklist = PyList_New(0);
+    if (weaklist == NULL)
+        PyErr_Clear();
+
+#define STORE_MODULE_WEAKREF(name, mod) \
+    if (weaklist != NULL) { \
+        PyObject *wr = PyWeakref_NewRef(mod, NULL); \
+        if (name && wr) { \
+            PyObject *tup = PyTuple_Pack(2, name, wr); \
+            PyList_Append(weaklist, tup); \
+            Py_XDECREF(tup); \
+        } \
+        Py_XDECREF(wr); \
+        if (PyErr_Occurred()) \
+            PyErr_Clear(); \
+    }
+
+    /* Remove __main__ module */
+    key = _PyUnicode_FromId(&PyId___main__);
+    if (key != NULL)
+        value = PyDict_GetItemWithError(modules, key);
+    else
+        value = NULL;
+    if (value != NULL) {
+        if (PyModule_Check(value)) {
+            if (Py_VerboseFlag)
+                PySys_FormatStderr("# cleanup[2] removing %U\n", key);
+            STORE_MODULE_WEAKREF(key, value);
+            PyDict_SetItem(modules, key, Py_None);
+        }
+    }
+    else
+        PyErr_Clear();
+
     /* Delete some special variables first.  These are common
        places where user values hide and people complain when their
        destructors fail.  Since the modules containing them are
@@ -375,27 +414,6 @@ PyImport_Cleanup(void)
         PyDict_SetItemString(interp->sysdict, *p, value);
     }
 
-    /* We prepare a list which will receive (name, weakref) tuples of
-       modules when they are removed from sys.modules.  The name is used
-       for diagnosis messages (in verbose mode), while the weakref helps
-       detect those modules which have been held alive. */
-    weaklist = PyList_New(0);
-    if (weaklist == NULL)
-        PyErr_Clear();
-
-#define STORE_MODULE_WEAKREF(name, mod) \
-    if (weaklist != NULL) { \
-        PyObject *wr = PyWeakref_NewRef(mod, NULL); \
-        if (name && wr) { \
-            PyObject *tup = PyTuple_Pack(2, name, wr); \
-            PyList_Append(weaklist, tup); \
-            Py_XDECREF(tup); \
-        } \
-        Py_XDECREF(wr); \
-        if (PyErr_Occurred()) \
-            PyErr_Clear(); \
-    }
-
     /* Remove all modules from sys.modules, hoping that garbage collection
        can reclaim most of them. */
     pos = 0;