1 files changed, 1 insertions, 0 deletions
diff --git a/src/treegen.h b/src/treegen.h
index 16c85cf0a..55da6f9e5 100644
--- a/src/treegen.h
+++ b/src/treegen.h
@@ -25,6 +25,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 class ManualMapVoxelManipulator;
 class INodeDefManager;
+class ServerEnvironment;
 
 
 namespace treegen {