diff --git a/src/gn/err.h b/src/gn/err.h
index efccf0b..662d8b5 100644
--- a/src/gn/err.h
+++ b/src/gn/err.h
@@ -5,6 +5,7 @@
 #ifndef TOOLS_GN_ERR_H_
 #define TOOLS_GN_ERR_H_
 
+#include <memory>
 #include <string>
 #include <vector>