diff --git a/loader/module.c b/loader/module.c
index 637c693..e291b0d 100644
--- a/loader/module.c
+++ b/loader/module.c
@@ -18,13 +18,17 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#include "config.h"
+
 #include <assert.h>
 #include <fcntl.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/types.h>
-#include <unistd.h>
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
 #include "wine/winbase16.h"
 #include "winerror.h"
 #include "heap.h"