diff --git a/include/xo/type/array/IGCObject_DArrayType.hpp b/include/xo/type/array/IGCObject_DArrayType.hpp
index 28f0dcca..fe1e8b13 100644
--- a/include/xo/type/array/IGCObject_DArrayType.hpp
+++ b/include/xo/type/array/IGCObject_DArrayType.hpp
@@ -48,8 +48,6 @@ namespace xo {
             /** @defgroup scm-gcobject-darraytype-methods **/
             ///@{
             // const methods
-            /** memory consumption for this instance **/
-            static size_type shallow_size(const DArrayType & self) noexcept;
 
             // non-const methods
             /** move instance using allocator **/
diff --git a/include/xo/type/atomic/IGCObject_DAtomicType.hpp b/include/xo/type/atomic/IGCObject_DAtomicType.hpp
index e5652bf6..844c21cc 100644
--- a/include/xo/type/atomic/IGCObject_DAtomicType.hpp
+++ b/include/xo/type/atomic/IGCObject_DAtomicType.hpp
@@ -48,8 +48,6 @@ namespace xo {
             /** @defgroup scm-gcobject-datomictype-methods **/
             ///@{
             // const methods
-            /** memory consumption for this instance **/
-            static size_type shallow_size(const DAtomicType & self) noexcept;
 
             // non-const methods
             /** move instance using allocator **/
diff --git a/include/xo/type/function/IGCObject_DFunctionType.hpp b/include/xo/type/function/IGCObject_DFunctionType.hpp
index 0c77e475..19c9b7da 100644
--- a/include/xo/type/function/IGCObject_DFunctionType.hpp
+++ b/include/xo/type/function/IGCObject_DFunctionType.hpp
@@ -48,8 +48,6 @@ namespace xo {
             /** @defgroup scm-gcobject-dfunctiontype-methods **/
             ///@{
             // const methods
-            /** memory consumption for this instance **/
-            static size_type shallow_size(const DFunctionType & self) noexcept;
 
             // non-const methods
             /** move instance using allocator **/
diff --git a/include/xo/type/list/IGCObject_DListType.hpp b/include/xo/type/list/IGCObject_DListType.hpp
index 322fc2da..19450270 100644
--- a/include/xo/type/list/IGCObject_DListType.hpp
+++ b/include/xo/type/list/IGCObject_DListType.hpp
@@ -48,8 +48,6 @@ namespace xo {
             /** @defgroup scm-gcobject-dlisttype-methods **/
             ///@{
             // const methods
-            /** memory consumption for this instance **/
-            static size_type shallow_size(const DListType & self) noexcept;
 
             // non-const methods
             /** move instance using allocator **/
diff --git a/include/xo/type/typevar/IGCObject_DTypeVarRef.hpp b/include/xo/type/typevar/IGCObject_DTypeVarRef.hpp
index 94be0f90..caf35660 100644
--- a/include/xo/type/typevar/IGCObject_DTypeVarRef.hpp
+++ b/include/xo/type/typevar/IGCObject_DTypeVarRef.hpp
@@ -48,8 +48,6 @@ namespace xo {
             /** @defgroup scm-gcobject-dtypevarref-methods **/
             ///@{
             // const methods
-            /** memory consumption for this instance **/
-            static size_type shallow_size(const DTypeVarRef & self) noexcept;
 
             // non-const methods
             /** move instance using allocator **/
diff --git a/src/type/IGCObject_DArrayType.cpp b/src/type/IGCObject_DArrayType.cpp
index 31867406..5f9e6c23 100644
--- a/src/type/IGCObject_DArrayType.cpp
+++ b/src/type/IGCObject_DArrayType.cpp
@@ -15,12 +15,6 @@
 
 namespace xo {
     namespace scm {
-        auto
-        IGCObject_DArrayType::shallow_size(const DArrayType & self) noexcept -> size_type
-        {
-            return self.shallow_size();
-        }
-
         auto
         IGCObject_DArrayType::shallow_move(DArrayType & self, obj<ACollector> gc) noexcept -> Opaque
         {
diff --git a/src/type/IGCObject_DAtomicType.cpp b/src/type/IGCObject_DAtomicType.cpp
index 533f017e..287db903 100644
--- a/src/type/IGCObject_DAtomicType.cpp
+++ b/src/type/IGCObject_DAtomicType.cpp
@@ -15,12 +15,6 @@
 
 namespace xo {
     namespace scm {
-        auto
-        IGCObject_DAtomicType::shallow_size(const DAtomicType & self) noexcept -> size_type
-        {
-            return self.shallow_size();
-        }
-
         auto
         IGCObject_DAtomicType::shallow_move(DAtomicType & self, obj<ACollector> gc) noexcept -> Opaque
         {
diff --git a/src/type/IGCObject_DFunctionType.cpp b/src/type/IGCObject_DFunctionType.cpp
index 4a44fd3b..3114a00d 100644
--- a/src/type/IGCObject_DFunctionType.cpp
+++ b/src/type/IGCObject_DFunctionType.cpp
@@ -15,12 +15,6 @@
 
 namespace xo {
     namespace scm {
-        auto
-        IGCObject_DFunctionType::shallow_size(const DFunctionType & self) noexcept -> size_type
-        {
-            return self.shallow_size();
-        }
-
         auto
         IGCObject_DFunctionType::shallow_move(DFunctionType & self, obj<ACollector> gc) noexcept -> Opaque
         {
diff --git a/src/type/IGCObject_DListType.cpp b/src/type/IGCObject_DListType.cpp
index 7cabe586..bf5860f1 100644
--- a/src/type/IGCObject_DListType.cpp
+++ b/src/type/IGCObject_DListType.cpp
@@ -15,12 +15,6 @@
 
 namespace xo {
     namespace scm {
-        auto
-        IGCObject_DListType::shallow_size(const DListType & self) noexcept -> size_type
-        {
-            return self.shallow_size();
-        }
-
         auto
         IGCObject_DListType::shallow_move(DListType & self, obj<ACollector> gc) noexcept -> Opaque
         {
diff --git a/src/type/IGCObject_DTypeVarRef.cpp b/src/type/IGCObject_DTypeVarRef.cpp
index 0dc4469c..910b7a9d 100644
--- a/src/type/IGCObject_DTypeVarRef.cpp
+++ b/src/type/IGCObject_DTypeVarRef.cpp
@@ -15,12 +15,6 @@
 
 namespace xo {
     namespace scm {
-        auto
-        IGCObject_DTypeVarRef::shallow_size(const DTypeVarRef & self) noexcept -> size_type
-        {
-            return self.shallow_size();
-        }
-
         auto
         IGCObject_DTypeVarRef::shallow_move(DTypeVarRef & self, obj<ACollector> gc) noexcept -> Opaque
         {