1 files changed, 2 insertions, 0 deletions
diff --git a/src/expr.cc b/src/expr.cc
index c8945d3d..c19bba98 100644
--- a/src/expr.cc
+++ b/src/expr.cc
@@ -35,6 +35,8 @@
 #include "parser.h"
 #include "scope.h"
 
+#include <boost/smart_ptr/scoped_ptr.hpp>
+
 namespace ledger {
 
 expr_t::expr_t() : base_type()