diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index aabf20b8d96..f4d2716fe30 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -22,9 +22,15 @@ Copyright (C) 1994 Steen Lumholt.
 */
 
 #define PY_SSIZE_T_CLEAN
+#ifndef Py_BUILD_CORE_BUILTIN
+#  define Py_BUILD_CORE_MODULE 1
+#endif
 
 #include "Python.h"
 #include <ctype.h>
+#ifdef MS_WINDOWS
+#  include "pycore_fileutils.h"   // _Py_stat()
+#endif
 
 #ifdef MS_WINDOWS
 #include <windows.h>
diff --git a/PC/_testconsole.c b/PC/_testconsole.c
index db84f73c774..a8308835d8f 100644
--- a/PC/_testconsole.c
+++ b/PC/_testconsole.c
@@ -1,11 +1,15 @@
-
 /* Testing module for multi-phase initialization of extension modules (PEP 489)
  */
 
+#ifndef Py_BUILD_CORE_BUILTIN
+#  define Py_BUILD_CORE_MODULE 1
+#endif
+
 #include "Python.h"
 
 #ifdef MS_WINDOWS
 
+#include "pycore_fileutils.h"     // _Py_get_osfhandle()
 #include "..\modules\_io\_iomodule.h"
 
 #define WIN32_LEAN_AND_MEAN