diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 0d0579c5e..926f6e722 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,7 @@
+2003-12-16  Corinna Vinschen  <corinna@vinschen.de>
+
+	* include/cygwin/ipc.h: Include sys/types.h.
+
 2003-12-15  Thomas Pfaff  <tpfaff@gmx.net>
 
 	* thread.cc (pthread::init_main_thread): Make sure that the main thread
diff --git a/winsup/cygwin/include/cygwin/ipc.h b/winsup/cygwin/include/cygwin/ipc.h
index 31b79ffd4..90534c29d 100644
--- a/winsup/cygwin/include/cygwin/ipc.h
+++ b/winsup/cygwin/include/cygwin/ipc.h
@@ -12,6 +12,8 @@ details. */
 #ifndef _CYGWIN_IPC_H
 #define _CYGWIN_IPC_H
 
+#include <sys/types.h>
+
 #ifdef __cplusplus
 extern "C"
 {