diff --git a/siplib/siplib.c b/siplib/siplib.c
index b891f79..f2ac7be 100644
--- a/siplib/siplib.c
+++ b/siplib/siplib.c
@@ -7488,7 +7488,7 @@ static int compareTypeDef(const void *key, const void *el)
         /* Find which external type it is. */
         while (etd->et_nr >= 0)
         {
-            const sipTypeDef **tdp = &module_searched->em_types[etd->et_nr];
+            const sipTypeDef **tdp = (const sipTypeDef**)&module_searched->em_types[etd->et_nr];
 
             if (tdp == (const sipTypeDef **)el)
             {
@@ -8485,9 +8485,9 @@ static void sipSimpleWrapper_releasebuffer(sipSimpleWrapper *self,
     const sipClassTypeDef *ctd;
 
     if ((ptr = getPtrTypeDef(self, &ctd)) == NULL)
-        return -1;
+        return;
 
-    return ctd->ctd_releasebuffer((PyObject *)self, ptr, buf);
+    ctd->ctd_releasebuffer((PyObject *)self, ptr, buf);
 }
 
 
@@ -9762,7 +9762,7 @@ static int convertToWCharArray(PyObject *obj, wchar_t **ap, SIP_SSIZE_T *aszp)
     if ((wc = sip_api_malloc(ulen * sizeof (wchar_t))) == NULL)
         return -1;
 
-    ulen = PyUnicode_AsWideChar((PyUnicodeObject *)obj, wc, ulen);
+    ulen = PyUnicode_AsWideChar(obj, wc, ulen);
 
     if (ulen < 0)
     {
@@ -9797,7 +9797,7 @@ static int convertToWChar(PyObject *obj, wchar_t *ap)
     if (PyUnicode_GET_LENGTH(obj) != 1)
         return -1;
 
-    if (PyUnicode_AsWideChar((PyUnicodeObject *)obj, ap, 1) != 1)
+    if (PyUnicode_AsWideChar(obj, ap, 1) != 1)
         return -1;
 
     return 0;
@@ -9837,7 +9837,7 @@ static int convertToWCharString(PyObject *obj, wchar_t **ap)
     if ((wc = sip_api_malloc((ulen + 1) * sizeof (wchar_t))) == NULL)
         return -1;
 
-    ulen = PyUnicode_AsWideChar((PyUnicodeObject *)obj, wc, ulen);
+    ulen = PyUnicode_AsWideChar(obj, wc, ulen);
 
     if (ulen < 0)
     {
diff --git a/siplib/tqtlib.c b/siplib/tqtlib.c
index df35d6c..d59c138 100644
--- a/siplib/tqtlib.c
+++ b/siplib/tqtlib.c
@@ -143,7 +143,7 @@ PyObject *sip_api_invoke_slot(const sipSlot *slot, PyObject *sigargs)
          * longer exists.
          */
         if (PyObject_TypeCheck(self, (PyTypeObject *)&sipSimpleWrapper_Type) &&
-            sip_api_get_address(self) == NULL)
+            sip_api_get_address((sipSimpleWrapper *)self) == NULL)
         {
             Py_XDECREF(sref);