diff --git a/reactos/regtests/shared/rtshared.xml b/reactos/regtests/shared/rtshared.xml
index eb58e6524d7..6e876c9e613 100644
--- a/reactos/regtests/shared/rtshared.xml
+++ b/reactos/regtests/shared/rtshared.xml
@@ -1,4 +1,5 @@
 <module name="rtshared" type="staticlibrary">
 	<include base="rtshared">.</include>
+	<define name="__USE_W32API" />
 	<file>regtests.c</file>
 </module>