diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index c6bb16c..ca40cb0 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -511,7 +511,7 @@
 
     if (PyUnicode_Check(cmd)) {
         cf->cf_flags |= PyCF_IGNORE_COOKIE;
-        cmd = _PyUnicode_AsDefaultEncodedString(cmd, NULL);
+        cmd = _PyUnicode_AsDefaultEncodedString(cmd);
         if (cmd == NULL)
             return NULL;
     }
diff --git a/Python/compile.c b/Python/compile.c
index 1d6e38c..53f5a12 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -3026,7 +3026,7 @@
     case Name_kind:
         /* optimize away names that can't be reassigned */
         id = PyBytes_AS_STRING(
-            _PyUnicode_AsDefaultEncodedString(e->v.Name.id, NULL));
+            _PyUnicode_AsDefaultEncodedString(e->v.Name.id));
         if (strcmp(id, "True") == 0) return 1;
         if (strcmp(id, "False") == 0) return 0;
         if (strcmp(id, "None") == 0) return 0;
diff --git a/Python/getargs.c b/Python/getargs.c
index 17d5993..e1cef0c 100644
--- a/Python/getargs.c
+++ b/Python/getargs.c
@@ -551,7 +551,7 @@
 
 
 #define UNICODE_DEFAULT_ENCODING(arg) \
-    _PyUnicode_AsDefaultEncodedString(arg, NULL)
+    _PyUnicode_AsDefaultEncodedString(arg)
 
 /* Format an error message generated by convertsimple(). */