diff --git a/src/libutil/namespaces.cc b/src/libutil/namespaces.cc
index 222f0d11b..b1cdbfe03 100644
--- a/src/libutil/namespaces.cc
+++ b/src/libutil/namespaces.cc
@@ -1,11 +1,11 @@
+#if __linux__
+
 #include "namespaces.hh"
 #include "util.hh"
 #include "finally.hh"
 
 #include <mntent.h>
 
-#if __linux__
-
 namespace nix {
 
 bool userNamespacesSupported()