Bug with omitted optional intent out arguments of an abstract type

[Nicholas_B_]

The Intel Parallel Studio XE 2017 Fortran compiler produces code which crashes with omitted optional intent out arguments of an abstract type.

The previous version of the compiler did not have this problem:

forrtl: severe (157): Program Exception - access violation

program prog

  use sub_module
  use simple_exception_module

  implicit none

  type(simple_exception_type) :: exception
  character(:), allocatable :: message

  call sub( exception )
  if ( exception%catch( message ) ) then
    write(*,*) message
  end if

  call sub() ! crashes here

end program prog

module sub_module

  use exception_module

  implicit none
  
contains

  subroutine sub( exception )
    class(exception_type), intent(out), optional :: exception

    if ( present( exception ) ) then
      call exception%throw( 'Exception in sub' )
    end if
    
  end subroutine sub

end module sub_module

module simple_exception_module

  use exception_module

  implicit none
  private

  type, extends(exception_type), public :: simple_exception_type
    character(:), allocatable, private :: message
  contains
    procedure :: throw
    procedure :: catch
  end type simple_exception_type

contains

  subroutine throw( exception, message )
    class(simple_exception_type), intent(inout) :: exception
    character(*), intent(in) :: message
    exception%message = message
  end subroutine throw
    
  logical function catch( exception, message )
    class(simple_exception_type), intent(inout) :: exception
    character(:), allocatable, intent(out) :: message
    if ( allocated( exception%message ) ) then
      message = exception%message
      catch = .true.
    else
      catch = .false.
    end if
  end function catch
  
end module simple_exception_module

module exception_module

  implicit none

  type, abstract :: exception_type
  contains
    procedure(throw_proc), deferred :: throw
    procedure(catch_proc), deferred :: catch
  end type exception_type

  abstract interface
    subroutine throw_proc( exception, message )
      import
      class(exception_type), intent(inout) :: exception
      character(*), intent(in) :: message
    end subroutine throw_proc
  end interface
  
  abstract interface
    logical function catch_proc( exception, message )
      import
      class(exception_type), intent(inout) :: exception
      character(:), allocatable, intent(out) :: message
    end function catch_proc
  end interface
  
end module exception_module

[Steven_L_Intel1]

Thanks - I can reproduce this and will send it on to the developers. Issue ID DPD200414727

[Steven_L_Intel1]

I expect this bug to be fixed in Update 2 to Parallel Studio XE 2017.