deallocating via pointer associated with allocatable array

From: Bart Vandewoestyne (MyFirstName.MyLastName_at_telenet.be)
Date: 03/23/05 

Date: Wed, 23 Mar 2005 16:26:30 +0000 (UTC)

Section 6.5.3 in Fortran 95/2003 explained:

"Its general form is

deallocate(allocate-object-list [,stat=stat])

where each allocate-object is an allocatable array that is allocated or
a pointer that is associated with the whole of a target that was
allocated through a pointer in an allocate statement \footnote{Note that
this excludes a pointer that is associated with an allocatable array}"

Does this mean the deallocate statement at the end of the following program
falls under this exception in the footnote and should therefore give compiler
errors/warnings or runtime errors or something alike?

program test_deallocate

  implicit none

  ! The allocatable array we are gonna point to
  integer, dimension(:), allocatable, target :: the_target

  ! The pointer that is gonna point to our allocatable array
  integer, dimension(:), pointer :: p

  ! Allocate memory for our allocatable array
  allocate(the_target(10))

  ! Now associate the pointer with this allocatable array
  p => the_target

  ! Deallocating through the pointer seems to work... ???
  deallocate(p)

end program test_deallocate

I am asking this because somewhere in my bigger code i had something like:

      real(kind=dp), dimension(:), allocatable, target :: temp

and in the code i had a pointer pointing to this allocatable, and then I tried
to deallocate the memory through a deallocate of the pointer. When i ran my
code, i got:

Pointer in DEALLOCATE is ASSOCIATED with an ALLOCATABLE array
Program terminated by fatal error
Aborted

Changing the declaration of temp into:

      real(kind=dp), dimension(:), pointer :: temp

solves my problem, but of course I wanted to understand exactly why, and i
tried to write a simple testcase which suffers from the same error
(see the above program), but apparently there still must be something
wrong as when I try to run my testprogram i cannot reproduce the error as above.
I don't see what is wrong with my simple testcase, since i am trying to
deallocate through a pointer which is associated with an allocatable array,
isn't it? Then why don't i get the same runtime error as cited above?

Regards,
Bart

PS: I am compiling with
Fortran Company/NAG F compiler Release 20020224 

-- 
	"Share what you know.  Learn what you don't."

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