diff --git a/compiler/cpp/src/parse/t_struct.h b/compiler/cpp/src/parse/t_struct.h
index aeee112..b82933d 100644
--- a/compiler/cpp/src/parse/t_struct.h
+++ b/compiler/cpp/src/parse/t_struct.h
@@ -43,11 +43,13 @@
   t_struct(t_program* program) :
     t_type(program),
     is_xception_(false),
+    is_union_(false),
     xsd_all_(false) {}
 
   t_struct(t_program* program, const std::string& name) :
     t_type(program, name),
     is_xception_(false),
+    is_union_(false),
     xsd_all_(false) {}
 
   void set_name(const std::string& name) {