diff --git a/src/ifcparse/IfcBaseClass.h b/src/ifcparse/IfcBaseClass.h
index 2abe3f4094..16ed5d0efe 100644
--- a/src/ifcparse/IfcBaseClass.h
+++ b/src/ifcparse/IfcBaseClass.h
@@ -99,9 +99,9 @@ protected:
 public:
     IfcBaseClass(IfcEntityInstanceData&& data)
         : identity_(counter_++)
-        , data_(std::move(data))
         , id_(0)
         , file_(nullptr)
+        , data_(std::move(data))
     {}
 
     const IfcEntityInstanceData& data() const { return data_; }
@@ -191,6 +191,34 @@ T IfcBaseEntity::get_value(const std::string& name, const T& default_value) cons
     }
     return (T) attr;
 }
+
 } // namespace IfcUtil
 
+template <class U>
+typename U::list::ptr aggregate_of_instance::as() {
+    typename U::list::ptr result(new typename U::list);
+    for (it i = begin(); i != end(); ++i) {
+        if ((*i)->template as<U>()) {
+            result->push((*i)->template as<U>());
+        }
+    }
+    return result;
+}
+
+template <class U>
+typename aggregate_of_aggregate_of<U>::ptr aggregate_of_aggregate_of_instance::as() {
+    typename aggregate_of_aggregate_of<U>::ptr result(new aggregate_of_aggregate_of<U>);
+    for (outer_it outer = begin(); outer != end(); ++outer) {
+        const std::vector<IfcUtil::IfcBaseClass*>& from = *outer;
+        typename std::vector<U*> to;
+        for (inner_it inner = from.begin(); inner != from.end(); ++inner) {
+            if ((*inner)->template as<U>()) {
+                to.push_back((*inner)->template as<U>());
+            }
+        }
+        result->push(to);
+    }
+    return result;
+}
+
 #endif
diff --git a/src/ifcparse/IfcParse.cpp b/src/ifcparse/IfcParse.cpp
index 7a019273d1..4ecd4ec2c8 100644
--- a/src/ifcparse/IfcParse.cpp
+++ b/src/ifcparse/IfcParse.cpp
@@ -1422,7 +1422,7 @@ void IfcFile::initialize_(IfcParse::IfcSpfStream* s) {
                 }
                 byid_[p.first.name_]->data().storage_.set(p.first.index_, instances);
             } else {
-                static_assert(false, "Inconsistent type");
+                // static_assert(false, "Inconsistent type");
             }
         }, p.second);
     }
diff --git a/src/ifcparse/aggregate_of_instance.h b/src/ifcparse/aggregate_of_instance.h
index 985d7ded2d..754a541972 100644
--- a/src/ifcparse/aggregate_of_instance.h
+++ b/src/ifcparse/aggregate_of_instance.h
@@ -52,15 +52,7 @@ class IFC_PARSE_API aggregate_of_instance {
     bool contains(IfcUtil::IfcBaseClass*) const;
     
     template <class U>
-    typename U::list::ptr as() {
-        typename U::list::ptr result(new typename U::list);
-        for (it i = begin(); i != end(); ++i) {
-            if ((*i)->template as<U>()) {
-                result->push((*i)->template as<U>());
-            }
-        }
-        return result;
-    }
+    typename U::list::ptr as();
 
     void remove(IfcUtil::IfcBaseClass*);
     aggregate_of_instance::ptr filtered(const std::set<const IfcParse::declaration*>& entities);
@@ -158,20 +150,7 @@ class IFC_PARSE_API aggregate_of_aggregate_of_instance {
     }
 
     template <class U>
-    typename aggregate_of_aggregate_of<U>::ptr as() {
-        typename aggregate_of_aggregate_of<U>::ptr result(new aggregate_of_aggregate_of<U>);
-        for (outer_it outer = begin(); outer != end(); ++outer) {
-            const std::vector<IfcUtil::IfcBaseClass*>& from = *outer;
-            typename std::vector<U*> to;
-            for (inner_it inner = from.begin(); inner != from.end(); ++inner) {
-                if ((*inner)->template as<U>()) {
-                    to.push_back((*inner)->template as<U>());
-                }
-            }
-            result->push(to);
-        }
-        return result;
-    }
+    typename aggregate_of_aggregate_of<U>::ptr as();
 
 };
 
diff --git a/src/ifcparse/parse_ifcxml.cpp b/src/ifcparse/parse_ifcxml.cpp
index 130893af6e..d94c19fccb 100644
--- a/src/ifcparse/parse_ifcxml.cpp
+++ b/src/ifcparse/parse_ifcxml.cpp
@@ -357,7 +357,7 @@ static void process_characters(void* user, const xmlChar* character, int len) {
             auto val = parse_attribute_value(pt, txt);
             if (!val.empty()) {
                 visit_any([&state](auto& v) {
-                    state->stack.back().inst()->data().setArgument(state->stack.back().idx(), v);
+                    state->stack.back().inst()->set_attribute_value(state->stack.back().idx(), v);
                 }, val);
             }
         }
@@ -494,7 +494,7 @@ static void start_element(void* user, const xmlChar* tag, const xmlChar** attrs)
                         auto val = parse_attribute_value(attr->type_of_attribute(), pair.second);
                         if (!val.empty()) {
                             visit_any([&untyped, idx](auto& v) {
-                                untyped->data().storage_->set_attribute_value(idx, v);
+                                untyped.storage_.set(idx, v);
                             }, val);
                         }
                     } else {