diff --git a/flang/runtime/assign.cpp b/flang/runtime/assign.cpp
--- a/flang/runtime/assign.cpp
+++ b/flang/runtime/assign.cpp
@@ -318,10 +318,10 @@
     // for all components, including parent components (10.2.1.2-3).
     // The target is first finalized if still necessary (7.5.6.3(1))
     if (needFinalization) {
-      Finalize(to, *toDerived);
+      Finalize(to, *toAddendum->derivedType());
     }
     // Copy the data components (incl. the parent) first.
-    const Descriptor &componentDesc{toDerived->component()};
+    const Descriptor &componentDesc{toAddendum->derivedType()->component()};
     std::size_t numComponents{componentDesc.Elements()};
     for (std::size_t k{0}; k < numComponents; ++k) {
       const auto &comp{
@@ -394,7 +394,7 @@
       }
     }
     // Copy procedure pointer components
-    const Descriptor &procPtrDesc{toDerived->procPtr()};
+    const Descriptor &procPtrDesc{toAddendum->derivedType()->procPtr()};
     std::size_t numProcPtrs{procPtrDesc.Elements()};
     for (std::size_t k{0}; k < numProcPtrs; ++k) {
       const auto &procPtr{