Propagate hierarchy helper template archument to IfcFile schema name

src/ifcparse/IfcHierarchyHelper.h

@@ -114,6 +114,8 @@ namespace {
 template <typename Schema>
 class IFC_PARSE_API IfcHierarchyHelper : public IfcParse::IfcFile {
 public:
+	IfcHierarchyHelper() : IfcParse::IfcFile(&Schema::get_schema()) {}
+
 	template <class T> 
 	T* addTriplet(double x, double y, double z) {
 		std::vector<double> a; a.push_back(x); a.push_back(y); a.push_back(z);