diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index 39a735b50e..433824044d 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -303,9 +303,7 @@ class Query(BaseExpression):
         obj.table_map = self.table_map.copy()
         obj.where = self.where.clone()
         obj.annotations = self.annotations.copy()
-        if self.annotation_select_mask is None:
-            obj.annotation_select_mask = None
-        else:
+        if self.annotation_select_mask is not None:
             obj.annotation_select_mask = self.annotation_select_mask.copy()
         obj.combined_queries = tuple(query.clone() for query in self.combined_queries)
         # _annotation_select_cache cannot be copied, as doing so breaks the
@@ -315,13 +313,9 @@ class Query(BaseExpression):
         # used.
         obj._annotation_select_cache = None
         obj.extra = self.extra.copy()
-        if self.extra_select_mask is None:
-            obj.extra_select_mask = None
-        else:
+        if self.extra_select_mask is not None:
             obj.extra_select_mask = self.extra_select_mask.copy()
-        if self._extra_select_cache is None:
-            obj._extra_select_cache = None
-        else:
+        if self._extra_select_cache is not None:
             obj._extra_select_cache = self._extra_select_cache.copy()
         if self.select_related is not False:
             # Use deepcopy because select_related stores fields in nested