diff --git a/flang/lib/Lower/ConvertVariable.cpp b/flang/lib/Lower/ConvertVariable.cpp
--- a/flang/lib/Lower/ConvertVariable.cpp
+++ b/flang/lib/Lower/ConvertVariable.cpp
@@ -726,11 +726,26 @@
           return;
       mlir::Location loc = converter.getCurrentLocation();
       fir::FirOpBuilder &builder = converter.getFirOpBuilder();
+      auto genDeallocateWithTypeDesc = [&]() {
+        if (mutBox->isPolymorphic()) {
+          mlir::Value declaredTypeDesc;
+          assert(sym.GetType());
+          if (const Fortran::semantics::DerivedTypeSpec *derivedTypeSpec =
+                  sym.GetType()->AsDerived()) {
+            declaredTypeDesc = Fortran::lower::getTypeDescAddr(
+                converter, loc, *derivedTypeSpec);
+          }
+          genDeallocateBox(converter, *mutBox, loc, declaredTypeDesc);
+        } else {
+          genDeallocateBox(converter, *mutBox, loc);
+        }
+      };
+
       if (Fortran::semantics::IsOptional(sym)) {
         auto isPresent = builder.create<fir::IsPresentOp>(
             loc, builder.getI1Type(), fir::getBase(extVal));
         builder.genIfThen(loc, isPresent)
-            .genThen([&]() { genDeallocateBox(converter, *mutBox, loc); })
+            .genThen([&]() { genDeallocateWithTypeDesc(); })
             .end();
       } else {
         if (mutBox->isDerived() || mutBox->isPolymorphic() ||
@@ -738,20 +753,7 @@
           mlir::Value isAlloc = fir::factory::genIsAllocatedOrAssociatedTest(
               builder, loc, *mutBox);
           builder.genIfThen(loc, isAlloc)
-              .genThen([&]() {
-                if (mutBox->isPolymorphic()) {
-                  mlir::Value declaredTypeDesc;
-                  assert(sym.GetType());
-                  if (const Fortran::semantics::DerivedTypeSpec
-                          *derivedTypeSpec = sym.GetType()->AsDerived()) {
-                    declaredTypeDesc = Fortran::lower::getTypeDescAddr(
-                        converter, loc, *derivedTypeSpec);
-                  }
-                  genDeallocateBox(converter, *mutBox, loc, declaredTypeDesc);
-                } else {
-                  genDeallocateBox(converter, *mutBox, loc);
-                }
-              })
+              .genThen([&]() { genDeallocateWithTypeDesc(); })
               .end();
         } else {
           genDeallocateBox(converter, *mutBox, loc);
diff --git a/flang/test/Lower/intentout-deallocate.f90 b/flang/test/Lower/intentout-deallocate.f90
--- a/flang/test/Lower/intentout-deallocate.f90
+++ b/flang/test/Lower/intentout-deallocate.f90
@@ -236,6 +236,20 @@
 ! CHECK:   %[[NULL_TYPE_DESC:.*]] = fir.zero_bits !fir.ref<none>  
 ! CHECK:   %[[BOX_NONE:.*]] = fir.convert %[[ARG0]] : (!fir.ref<!fir.class<!fir.heap<none>>>) -> !fir.ref<!fir.box<none>>
 ! CHECK:   %{{.*}} = fir.call @_FortranAAllocatableDeallocatePolymorphic(%[[BOX_NONE]], %[[NULL_TYPE_DESC]], %{{.*}}, %{{.*}}, %{{.*}}) {{.*}} : (!fir.ref<!fir.box<none>>, !fir.ref<none>, i1, !fir.box<none>, !fir.ref<i8>, i32) -> i32
+! CHECK: }
+
+  subroutine sub16(p)
+    class(t), optional, intent(out), allocatable :: p
+  end subroutine
+
+! CHECK-LABEL: func.func @_QMmod1Psub16(
+! CHECK-SAME: %[[ARG0:.*]]: !fir.ref<!fir.class<!fir.heap<!fir.type<_QMmod1Tt{a:i32}>>>> {fir.bindc_name = "p", fir.optional}) {
+! CHECK: %[[IS_PRESENT:.*]] = fir.is_present %[[ARG0]] : (!fir.ref<!fir.class<!fir.heap<!fir.type<_QMmod1Tt{a:i32}>>>>) -> i1
+! CHECK: fir.if %[[IS_PRESENT]] {
+! CHECK:   %[[TYPE_DESC:.*]] = fir.type_desc !fir.type<_QMmod1Tt{a:i32}>
+! CHECK:   %[[BOX_NONE:.*]] = fir.convert %[[ARG0]] : (!fir.ref<!fir.class<!fir.heap<!fir.type<_QMmod1Tt{a:i32}>>>>) -> !fir.ref<!fir.box<none>>
+! CHECK:   %[[TYPE_NONE:.*]] = fir.convert %[[TYPE_DESC]] : (!fir.tdesc<!fir.type<_QMmod1Tt{a:i32}>>) -> !fir.ref<none> 
+! CHECK:   %{{.*}} = fir.call @_FortranAAllocatableDeallocatePolymorphic(%[[BOX_NONE]], %[[TYPE_NONE]], %{{.*}}, %{{.*}}, %{{.*}}) {{.*}} : (!fir.ref<!fir.box<none>>, !fir.ref<none>, i1, !fir.box<none>, !fir.ref<i8>, i32) -> i32
 ! CHECK: }
 
 end module