1 files changed, 1 insertions, 1 deletions
diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index 03bf43a3b9a4..c7533479aa67 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -5,6 +5,7 @@
 
 #include "nixexpr.hh"
 #include "symbol-table.hh"
+#include "hash.hh"
 
 typedef union _ATermList * ATermList;
 
@@ -12,7 +13,6 @@ typedef union _ATermList * ATermList;
 namespace nix {
 
 
-class Hash;
 class EvalState;
 struct Env;
 struct Value;