diff --git a/src/calibre/utils/fonts/freetype.cpp b/src/calibre/utils/fonts/freetype.cpp
index 62314bfe2e..6e545f4ce5 100644
--- a/src/calibre/utils/fonts/freetype.cpp
+++ b/src/calibre/utils/fonts/freetype.cpp
@@ -309,10 +309,9 @@ exec_module(PyObject *m) {
 
 static PyModuleDef_Slot slots[] = { {Py_mod_exec, (void*)exec_module}, {0, NULL} };
 
-static struct PyModuleDef module_def = {{0}};
+static struct PyModuleDef module_def = {PyModuleDef_HEAD_INIT};
 
 CALIBRE_MODINIT_FUNC PyInit_freetype(void) {
-	module_def.m_base = PyModuleDef_HEAD_INIT;
 	module_def.m_name = "freetype";
 	module_def.m_doc = freetype_doc;
 	module_def.m_slots = slots;
diff --git a/src/calibre/utils/spell/hunspell_wrapper.cpp b/src/calibre/utils/spell/hunspell_wrapper.cpp
index 7e48dbe2be..371c65e963 100644
--- a/src/calibre/utils/spell/hunspell_wrapper.cpp
+++ b/src/calibre/utils/spell/hunspell_wrapper.cpp
@@ -184,10 +184,9 @@ exec_module(PyObject *mod) {
 
 static PyModuleDef_Slot slots[] = { {Py_mod_exec, (void*)exec_module}, {0, NULL} };
 
-static struct PyModuleDef module_def = {{0}};
+static struct PyModuleDef module_def = {PyModuleDef_HEAD_INIT};
 
 CALIBRE_MODINIT_FUNC PyInit_hunspell(void) {
-	module_def.m_base = PyModuleDef_HEAD_INIT;
 	module_def.m_name = "hunspell";
 	module_def.m_slots = slots;
 	return PyModuleDef_Init(&module_def);