diff --git a/compiler/cpp/src/main.h b/compiler/cpp/src/main.h
index 9a3a81e..a7c1d3d 100644
--- a/compiler/cpp/src/main.h
+++ b/compiler/cpp/src/main.h
@@ -2,6 +2,7 @@
 #define T_MAIN_H
 
 #include <string>
+#include "parse/t_const.h"
 
 /**
  * Defined in the flex library
@@ -29,7 +30,12 @@
 /**
  * Failure!
  */
-void failure(char* fmt, ...);
+void failure(const char* fmt, ...);
+
+/**
+ * Check constant types
+ */
+void validate_const_type(t_const* c);
 
 /**
  * Converts a string filename into a thrift program name