1 files changed, 1 insertions, 6 deletions
diff --git a/libbuild2/variable.hxx b/libbuild2/variable.hxx
index 51cdf49..6a2c681 100644
--- a/libbuild2/variable.hxx
+++ b/libbuild2/variable.hxx
@@ -14,6 +14,7 @@
 #include <libbutl/multi-index.mxx> // map_key
 
 #include <libbuild2/types.hxx>
+#include <libbuild2/forward.hxx>
 #include <libbuild2/utility.hxx>
 
 #include <libbuild2/context.hxx>
@@ -34,10 +35,6 @@ namespace build2
   //    during a phase other than load must make sure the variable has already
   //    been typified.
 
-  class value;
-  struct variable;
-  struct lookup;
-
   struct value_type
   {
     const char* name;  // Type name for diagnostics.
@@ -481,8 +478,6 @@ namespace build2
   // A variable can be undefined, NULL, or contain a (potentially empty)
   // value.
   //
-  class variable_map;
-
   struct lookup
   {
     using value_type = build2::value;