diff --git a/compiler/cpp/src/main.h b/compiler/cpp/src/main.h
index a7c1d3d..470ac7f 100644
--- a/compiler/cpp/src/main.h
+++ b/compiler/cpp/src/main.h
@@ -3,6 +3,7 @@
 
 #include <string>
 #include "parse/t_const.h"
+#include "parse/t_field.h"
 
 /**
  * Defined in the flex library
@@ -38,6 +39,11 @@
 void validate_const_type(t_const* c);
 
 /**
+ * Check constant types
+ */
+void validate_field_value(t_field* field, t_const_value* cv);
+
+/**
  * Converts a string filename into a thrift program name
  */
 std::string program_name(std::string filename);