LI76637: INTRINSIC ASSIGNMENT PROBLEM

June 2012 Update for XL Fortran for Linux, V13.1
October 2012 Update for XL Fortran for Linux, V13.1
XL Fortran for Linux Fix Pack 8 (June 2013 Update) for 13.1

APAR status

• Closed as program error.

Error description

• Consider the following test case that demonstrates the problem:
  
  ===== TEST CASE:
  $ cat test.F90
  module hermetic_module
   implicit none
   private
   public :: hermetic
   type,abstract::hermetic
   end type
  end module
  
  module ref_counter_module
   use hermetic_module, only: hermetic
   private
   public :: ref_counter
   type,extends(hermetic):: ref_counter
      private
      class(hermetic),pointer :: obj => null()
   contains
      procedure :: assign
      generic :: assignment(=) => assign
      final :: finalize_ref_counter
   end type
   interface ref_counter
       module procedure constructor
   end interface
  contains
  subroutine assign (lhs, rhs)
   class (ref_counter), intent(inout) :: lhs
   class (ref_counter), intent(in) :: rhs
   print *,'assign'
   lhs%obj => rhs%obj
   print *,'rhs:',associated(lhs%obj),associated(rhs%obj)
  end subroutine
  function constructor (object)
   class(hermetic), intent(in) :: object
   type(ref_counter), allocatable :: constructor
   print *,'constructor start'
   allocate (constructor)
   allocate (constructor%obj, source=object)
   print *,'constructor:',associated(constructor%obj)
  end function
  subroutine finalize_ref_counter(this)
   type(ref_counter), intent(inout) :: this
   print *,'finalize_ref_counter start'
     print *,'I could deallocate here'
   print *,'finalize_ref_counter ends'
  end subroutine
  end module
  
  module universal_module
   use hermetic_module ,only : hermetic
   use ref_counter_module, only : ref_counter
   implicit none
   type ,abstract ,extends(hermetic) :: universal
     private
     type(ref_counter) :: counter
     contains
     procedure,non_overridable:: register_self
   end type
  contains
  subroutine register_self(this)
   class(universal) ,intent(inout) :: this
   this%counter=ref_counter(this)
  end subroutine
  end module
  
  module map_module
  use universal_module, only: universal
  implicit none
  private
  public :: map
  type, extends(universal) :: map
   integer::id
  end type
  interface map
   module procedure new_map
  end interface
  contains
  type(map) function new_map()
   new_map%id=1
   call new_map%register_self()
  end function
  end module
  
  program main
  use map_module, only: map
  type(map):: m
  m=map()
  end
  
  
  Compile the test case with the version of XL Fortran for AIX,
  V13.1 compiler, released before the November 2011 PTF update:
  
  
  xlf2003 test.F90
  
  
  Run the executable program:
  
  ./a.out
   constructor start
   constructor: T
   assign
   rhs: T T
   finalize_ref_counter start
   I could deallocate here
   finalize_ref_counter ends
   assign
   rhs: T T
   finalize_ref_counter start
   I could deallocate here
   finalize_ref_counter ends
  
  
  Recompile the test case with the November 2011 PTF for XL
  Fortran for AIX, V13.1:
  
  xlf2003 test.F90
  
  
  Run executable:
  
  ./a.out
   constructor start
   constructor: T
   assign
   rhs: T T
   finalize_ref_counter start
   I could deallocate here
   finalize_ref_counter ends
   finalize_ref_counter start   <--- previously missed
   I could deallocate here      <--- finalization
   finalize_ref_counter ends    <--- in test case
   assign
   rhs: T T
   finalize_ref_counter start
   I could deallocate here
   finalize_ref_counter ends
  

Local fix

• N/A
  

Problem summary

• The compiler misses a case to finalize an object whose type is
  a derived type that has a component whose type has user defined
  finalization routine.
  

Problem conclusion

• The problem had been fixed.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  IV06767

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  XL FORTRAN LINU

• Fixed component ID

  5724X1600

Applicable component levels

• RD10 PSN IV06767

     UP06/09/13