RPC_WSTR is not available Visual Studio 2003 or earlier.

Hirokazu Yamamoto · Hirokazu Yamamoto · commit ab058ed3df64 · 2008-08-17T07:26:26.000Z
(Maybe I should have defined RPC_WSTR on old compiler,
but uuidcreate() is only place using it, so I simply replaced
with unsigned short *)
diff --git a/PC/_msi.c b/PC/_msi.c
@@ -18,7 +18,7 @@ static PyObject*
 uuidcreate(PyObject* obj, PyObject*args)
 {
     UUID result;
-    RPC_WSTR cresult;
+    unsigned short *cresult;
     PyObject *oresult;
     
     /* May return ok, local only, and no address.

Original file line number	Diff line number	Diff line change
`@@ -18,7 +18,7 @@ static PyObject*`
`18`	`18`	`uuidcreate(PyObject* obj, PyObject*args)`
`19`	`19`	`{`
`20`	`20`	`UUID result;`
`21`		`- RPC_WSTR cresult;`
	`21`	`+ unsigned short *cresult;`
`22`	`22`	`PyObject *oresult;`
`23`	`23`
`24`	`24`	`/* May return ok, local only, and no address.`