anchor.diff:    !---------------------------------------------------------------------------------------------------------------------------------
     endfunction Get_Unit
   
  -  elemental function Upper_Case(string)
  +! XLF error : "The result of an elemental function must be a nonpointer, nonallocatable scalar, and its type parameters must be constant expressions."
  +  function Upper_Case(string)
     !---------------------------------------------------------------------------------------------------------------------------------
     !< Function for converting lower case characters of a string to upper case ones.
     !<
  
positive.code:   !---------------------------------------------------------------------------------------------------------------------------------
    endsubroutine byte_update
  
    pure subroutine vtk_update(act,cf,Nvtk,vtk)
    !---------------------------------------------------------------------------------------------------------------------------------
    !< Subroutine for updating (adding and removing elements into) vtk array.
    !---------------------------------------------------------------------------------------------------------------------------------
  
negative.code:   integer(I4P),                     intent(INOUT):: cf         !< Current file index (for concurrent files IO).
    integer(I4P),                     intent(INOUT):: Nvtk       !< Number of (concurrent) VTK files.
    type(Type_VTK_File), allocatable, intent(INOUT):: vtk(:)     !< VTK files data.
    type(Type_VTK_File), allocatable               :: vtk_tmp(:) !< Temporary array of VTK files data.
    character(len=len(act))                        :: upper_act !< Converted string.
    !---------------------------------------------------------------------------------------------------------------------------------
  
    !---------------------------------------------------------------------------------------------------------------------------------
  ! XLF error: 1511-051 (S) The type of the SELECT CASE expression is invalid.
    upper_act = Upper_Case(trim(act))
    select case(upper_act)
    case('ADD')
      if (Nvtk>0_I4P) then
        allocate(vtk_tmp(1:Nvtk))
  