diff --git a/flang/lib/Lower/ConvertCall.cpp b/flang/lib/Lower/ConvertCall.cpp
--- a/flang/lib/Lower/ConvertCall.cpp
+++ b/flang/lib/Lower/ConvertCall.cpp
@@ -921,8 +921,9 @@
         entity.isParameter()) {
       // Make a copy in a temporary.
       auto copy = builder.create<hlfir::AsExprOp>(loc, entity);
+      mlir::Type storageType = entity.getType();
       hlfir::AssociateOp associate = hlfir::genAssociateExpr(
-          loc, builder, hlfir::Entity{copy}, dummyType, "adapt.valuebyref");
+          loc, builder, hlfir::Entity{copy}, storageType, "adapt.valuebyref");
       entity = hlfir::Entity{associate.getBase()};
       // Register the temporary destruction after the call.
       preparedDummy.setExprAssociateCleanUp(
diff --git a/flang/test/Lower/HLFIR/calls-constant-expr-arg-polymorphic.f90 b/flang/test/Lower/HLFIR/calls-constant-expr-arg-polymorphic.f90
new file mode 100644
--- /dev/null
+++ b/flang/test/Lower/HLFIR/calls-constant-expr-arg-polymorphic.f90
@@ -0,0 +1,29 @@
+! RUN: bbc -emit-fir -hlfir --polymorphic-type -o - %s | FileCheck %s
+
+! Test when constant argument are copied in memory
+! and passed to polymorphic arguments.
+! The copy is done in case the dummy later appear in a
+! copy-out that would create write to this memory location.
+  type t1
+    integer :: i
+  end type
+  type, extends(t1) :: t2
+    integer :: j
+  end type
+  interface
+  subroutine foo(x)
+    import :: t1
+    class(t1) :: x(:)
+  end subroutine
+  end interface
+
+  call foo([t2(0,0)])
+end
+! CHECK-LABEL:   func.func @_QQmain() {
+! CHECK:           %[[VAL_3:.*]]:2 = hlfir.declare %{{.*}}(%[[VAL_2:.*]]) {fortran_attrs = #fir.var_attrs<parameter>, uniq_name = "_QQro.1x_QFTt2.0"}
+! CHECK:           %[[VAL_4:.*]] = hlfir.as_expr %[[VAL_3]]#0 : (!fir.ref<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>) -> !hlfir.expr<1x!fir.type<_QFTt2{i:i32,j:i32}>>
+! CHECK:           %[[VAL_5:.*]]:3 = hlfir.associate %[[VAL_4]](%[[VAL_2]]) {uniq_name = "adapt.valuebyref"} : (!hlfir.expr<1x!fir.type<_QFTt2{i:i32,j:i32}>>, !fir.shape<1>) -> (!fir.ref<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>, !fir.ref<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>, i1)
+! CHECK:           %[[VAL_6:.*]] = fir.embox %[[VAL_5]]#0(%[[VAL_2]]) : (!fir.ref<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>, !fir.shape<1>) -> !fir.box<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>
+! CHECK:           %[[VAL_7:.*]] = fir.convert %[[VAL_6]] : (!fir.box<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>) -> !fir.class<!fir.array<?x!fir.type<_QFTt1{i:i32}>>>
+! CHECK:           fir.call @_QPfoo(%[[VAL_7]]) {{.*}}: (!fir.class<!fir.array<?x!fir.type<_QFTt1{i:i32}>>>) -> ()
+! CHECK:           hlfir.end_associate %[[VAL_5]]#1, %[[VAL_5]]#2 : !fir.ref<!fir.array<1x!fir.type<_QFTt2{i:i32,j:i32}>>>, i1