[flang] Don't fold STORAGE_SIZE() on polymorphic argument

[klausler]

Summary

More generally, don't return a successful result from
Fortran::evaluate::DynamicType::MeasureSizeInBytes() when the
type is polymorphic.

[clementval]

LGTM

flang/lib/Evaluate/type.cpp

case TypeCategory::Character:
     if (auto len{GetCharLength()}) {
       return Fold(context,
           Expr<SubscriptInteger>{
               context.targetCharacteristics().GetByteSize(category_, kind_)} *
               std::move(*len));
     }
     break;
   case TypeCategory::Derived:
-    if (derived_ && derived_->scope()) {
+    if (!IsPolymorphic() && derived_ && derived_->scope()) {
       auto size{derived_->scope()->size()};
       auto align{aligned ? derived_->scope()->alignment().value_or(0) : 0};
       auto alignedSize{align > 0 ? ((size + align - 1) / align) * align : size};
       return Expr<SubscriptInteger>{
           static_cast<ConstantSubscript>(alignedSize)};
     }
     break;
   }

flang/test/Evaluate/errors01.f90

 ! RUN: not %flang_fc1 %s 2>&1 | FileCheck %s
 ! Check errors found in folding
 ! TODO: test others emitted from flang/lib/Evaluate
 module m
+  type t
+    real x
+  end type t
  contains
   subroutine s1(a,b)
     real :: a(*), b(:)
     !CHECK: error: DIM=1 dimension is out of range for rank-1 assumed-size array
     integer :: ub1(ubound(a,1))
     !CHECK-NOT: error: DIM=1 dimension is out of range for rank-1 assumed-size array
     integer :: lb1(lbound(a,1))
     !CHECK: error: DIM=0 dimension is out of range for rank-1 array
subroutine s9
     !CHECK: error: SOURCE= argument to SPREAD has rank 15 but must have rank less than 15
     integer, parameter :: bad1 = spread(rank15, 1, 1)
     integer, parameter :: matrix(2, 2) = reshape([1, 2, 3, 4], [2, 2])
     !CHECK: error: DIM=0 argument to SPREAD must be between 1 and 3
     integer, parameter :: bad2 = spread(matrix, 0, 1)
     !CHECK: error: DIM=4 argument to SPREAD must be between 1 and 3
     integer, parameter :: bad3 = spread(matrix, 4, 1)
   end subroutine
+  subroutine s12(x,y)
+    class(t), intent(in) :: x
+    class(*), intent(in) :: y
+    !CHERK: error: Must be a constant value
+    integer, parameter :: bad1 = storage_size(x)
+    !CHERK: error: Must be a constant value
+    integer, parameter :: bad2 = storage_size(y)
+  end subroutine
   subroutine warnings
     real, parameter :: ok1 = scale(0.0, 99999) ! 0.0
     real, parameter :: ok2 = scale(1.0, -99999) ! 0.0
     !CHECK: SCALE intrinsic folding overflow
     real, parameter :: bad1 = scale(1.0, 99999)
     !CHECK: complex ABS intrinsic folding overflow
     real, parameter :: bad2 = abs(cmplx(huge(0.),huge(0.)))
     !CHECK: warning: overflow on REAL(8) to REAL(4) conversion
     x = 1.D40
   end subroutine
 end module