diff --git a/os/connection.c b/os/connection.c
index 6cd8bcf43..162e1d93e 100644
--- a/os/connection.c
+++ b/os/connection.c
@@ -923,7 +923,7 @@ ErrorConnMax(XtransConnInfo trans_conn)
         iov[0].iov_len = sz_xConnSetupPrefix;
         iov[0].iov_base = (char *) &csp;
         iov[1].iov_len = csp.lengthReason;
-        iov[1].iov_base = NOROOM;
+        iov[1].iov_base = (void *) NOROOM;
         iov[2].iov_len = (4 - (csp.lengthReason & 3)) & 3;
         iov[2].iov_base = pad;
         (void) _XSERVTransWritev(trans_conn, iov, 3);
diff --git a/os/xstrans.c b/os/xstrans.c
index 6348a6511..2bc79e7ae 100644
--- a/os/xstrans.c
+++ b/os/xstrans.c
@@ -5,9 +5,11 @@
 #include <X11/Xfuncproto.h>
 
 /* ErrorF is used by xtrans */
+#ifndef HAVE_DIX_CONFIG_H
 extern _X_EXPORT void
 ErrorF(const char *f, ...)
 _X_ATTRIBUTE_PRINTF(1, 2);
+#endif
 
 #define TRANS_REOPEN
 #define TRANS_SERVER