If I have an allocatable array of a finalizable derived type, will the finalizer be called on every individual element when the array goes out of scope?
Here is a small code example that illustrates the question:
module LeakyTypeModule
implicit none
private
type, public :: LeakyType
real, pointer :: dontLeakMe(:) => null()
contains
procedure :: New
final :: Finalizer
end type
contains
subroutine New(self, n)
class(LeakyType), intent(out) :: self
integer , intent(in) :: n
allocate(self%dontLeakMe(n))
self%dontLeakMe = 42.0
end subroutine
subroutine Finalizer(self)
type(LeakyType), intent(inout) :: self
if (associated(self%dontLeakMe)) deallocate(self%dontLeakMe)
end subroutine
end module
program leak
use LeakyTypeModule
implicit none
type(LeakyType), allocatable :: arr(:)
allocate(arr(1))
call arr(1)%New(1000)
deallocate(arr)
end program
Note that this program leaks the dontLeakMe array allocated in the New() method of LeakyType. At first this was a bit surprising for me but, then I discovered that the problem can be fixed by declaring the finalizer elemental. Both gfortran and ifort behave in the same way, so I assume this behaviour is following the Fortran 2003 standard.
Can anyone confirm this? To be honest I have a hard time time understanding what the standard says on this particular point.
Right now I also can't see much use in not declaring all my finalizers elemental. Does this have any application I'm overlooking?
