diff --git a/flang/lib/Optimizer/Dialect/FIRType.cpp b/flang/lib/Optimizer/Dialect/FIRType.cpp
--- a/flang/lib/Optimizer/Dialect/FIRType.cpp
+++ b/flang/lib/Optimizer/Dialect/FIRType.cpp
@@ -511,7 +511,8 @@
                        mlir::Type eleTy) {
   if (eleTy.isa<fir::RecordType, fir::SequenceType, fir::HeapType,
                 fir::PointerType, mlir::NoneType, mlir::IntegerType,
-                mlir::FloatType>())
+                mlir::FloatType, fir::CharacterType, fir::LogicalType,
+                fir::ComplexType, mlir::ComplexType>())
     return mlir::success();
   return emitError() << "invalid element type\n";
 }
diff --git a/flang/test/Fir/invalid-types.fir b/flang/test/Fir/invalid-types.fir
--- a/flang/test/Fir/invalid-types.fir
+++ b/flang/test/Fir/invalid-types.fir
@@ -166,4 +166,4 @@
 // -----
 
 // expected-error@+1 {{invalid element type}}
-func.func private @upe() -> !fir.class<!fir.logical<1>>
+func.func private @upe() -> !fir.class<!fir.box<i32>>
diff --git a/flang/test/Lower/polymorphic.f90 b/flang/test/Lower/polymorphic.f90
--- a/flang/test/Lower/polymorphic.f90
+++ b/flang/test/Lower/polymorphic.f90
@@ -249,4 +249,38 @@
 ! CHECK: %[[CONVERT:.*]] = fir.convert %3 : (!fir.ref<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> !fir.ptr<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>
 ! CHECK: fir.store %[[CONVERT]] to %[[PTR]] : !fir.ref<!fir.ptr<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>>
 
+  subroutine up_input(a)
+    class(*), intent(in) :: a
+  end subroutine
+
+  subroutine pass_trivial_to_up()
+    call up_input('hello')
+    call up_input(1)
+    call up_input(2.5)
+    call up_input(.true.)
+    call up_input((-1.0,3))
+  end subroutine
+
+! CHECK-LABEL: func.func @_QMpolymorphic_testPpass_trivial_to_up() {
+! CHECK: %[[CHAR:.*]] = fir.address_of(@_QQcl.{{.*}}) : !fir.ref<!fir.char<1,5>>
+! CHECK: %[[EMBOX:.*]] = fir.embox %[[CHAR]] : (!fir.ref<!fir.char<1,5>>) -> !fir.class<!fir.char<1,5>>
+! CHECK: %[[CONVERT:.*]] = fir.convert %[[EMBOX]] : (!fir.class<!fir.char<1,5>>) -> !fir.class<none>
+! CHECK: fir.call @_QMpolymorphic_testPup_input(%[[CONVERT]]) {{.*}} : (!fir.class<none>) -> ()
+
+! CHECK: %[[BOX_INT:.*]] = fir.embox %{{.*}} : (!fir.ref<i32>) -> !fir.class<i32>
+! CHECK: %[[UP:.*]] = fir.convert %[[BOX_INT]] : (!fir.class<i32>) -> !fir.class<none>
+! CHECK: fir.call @_QMpolymorphic_testPup_input(%[[UP]]) {{.*}} : (!fir.class<none>) -> ()
+
+! CHECK: %[[BOX_REAL:.*]] = fir.embox %{{.*}} : (!fir.ref<f32>) -> !fir.class<f32>
+! CHECK: %[[UP:.*]] = fir.convert %[[BOX_REAL]] : (!fir.class<f32>) -> !fir.class<none>
+! CHECK: fir.call @_QMpolymorphic_testPup_input(%[[UP]]) {{.*}} : (!fir.class<none>) -> ()
+
+! CHECK: %[[BOX_LOG:.*]] = fir.embox %{{.*}} : (!fir.ref<!fir.logical<4>>) -> !fir.class<!fir.logical<4>>
+! CHECK: %[[UP:.*]] = fir.convert %[[BOX_LOG]] : (!fir.class<!fir.logical<4>>) -> !fir.class<none>
+! CHECK: fir.call @_QMpolymorphic_testPup_input(%[[UP]]) {{.*}} : (!fir.class<none>) -> ()
+
+! CHECK: %[[BOX_COMPLEX:.*]] = fir.embox %{{.*}} : (!fir.ref<!fir.complex<4>>) -> !fir.class<!fir.complex<4>>
+! CHECK: %[[UP:.*]] = fir.convert %[[BOX_COMPLEX]] : (!fir.class<!fir.complex<4>>) -> !fir.class<none>
+! CHECK: fir.call @_QMpolymorphic_testPup_input(%[[UP]]) {{.*}} : (!fir.class<none>) -> ()
+
 end module