gh-152433: Windows: _ctypes module: improve UWP compatibility (#152792)

Author: thexai

Misc/NEWS.d/next/Windows/2026-07-01-17-00-52.gh-issue-152433.kSd1bW.rst

@@ -0,0 +1 @@
+Allow build :mod:`!_ctypes` for Universal Windows Platform.

Modules/_ctypes/callproc.c

@@ -1082,8 +1082,7 @@ void _ctypes_extend_error(PyObject *exc_class, const char *fmt, ...)
 }
 
 
-#ifdef MS_WIN32
-
+#ifdef MS_WINDOWS_DESKTOP
 static PyObject *
 GetComError(ctypes_state *st, HRESULT errcode, GUID *riid, IUnknown *pIunk)
 {
@@ -1337,9 +1336,11 @@ PyObject *_ctypes_callproc(ctypes_state *st,
 
 #ifdef MS_WIN32
     if (iid && pIunk) {
+#ifdef MS_WINDOWS_DESKTOP
         if (*(int *)resbuf & 0x80000000)
             retval = GetComError(st, *(HRESULT *)resbuf, iid, pIunk);
         else
+#endif
             retval = PyLong_FromLong(*(int *)resbuf);
     } else if (flags & FUNCFLAG_HRESULT) {
         if (*(int *)resbuf & 0x80000000)