diff --git a/src/os/filestore/HashIndex.cc b/src/os/filestore/HashIndex.cc
index b0f93b9e258..e0d38f4bdc2 100644
--- a/src/os/filestore/HashIndex.cc
+++ b/src/os/filestore/HashIndex.cc
@@ -12,6 +12,7 @@
  *
  */
 
+#include "include/compat.h"
 #include "include/types.h"
 #include "include/buffer.h"
 #include "osd/osd_types.h"