diff --git a/indra/llcommon/lluuid.h b/indra/llcommon/lluuid.h
index 68e403fd4f23b595cd940d88d995275d37891900..c78fb1201804686242792e28950e4a340f4a1cc8 100644
--- a/indra/llcommon/lluuid.h
+++ b/indra/llcommon/lluuid.h
@@ -35,6 +35,7 @@
 #include <iostream>
 #include <set>
 #include "stdtypes.h"
+#include "llpreprocessor.h"
 
 const S32 UUID_BYTES = 16;
 const S32 UUID_WORDS = 4;