diff --git a/Objects/setobject.c b/Objects/setobject.c
index 8a2f351..f44f562 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -337,6 +337,7 @@
         return DISCARD_NOTFOUND;
     old_key = entry->key;
     entry->key = dummy;
+    entry->hash = -1;
     so->used--;
     Py_DECREF(old_key);
     return DISCARD_FOUND;
@@ -621,6 +622,7 @@
     }
     key = entry->key;
     entry->key = dummy;
+    entry->hash = -1;
     so->used--;
     so->finger = i + 1;         /* next place to start */
     return key;