[Bug fortran/47844] Array stride ignored for pointer-valued function results

["pault at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47844

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot       |pault at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #9 from Paul Thomas <pault at gcc dot gnu.org> 2011-10-05 22:20:13 UTC ---
Created attachment 25425
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25425
a draft patch for the pr

This has been partially regtested and looks OK at 20k tests or so - I had to
head off to bed!

If all is well, I will look for a slightly cleaner place to use the returned
stride; this place might not exist of course!

I will submit tomorrow with the test case below.

Cheers

Paul

! (dg-do run }
! Test the fix for PR47844, in which the stride in the function result
! was ignored. Previously, the result was [1,3] at lines 15 and 16.
!
! Contributed by KePu  <Kdx1999@gmail.com>
!
PROGRAM test_pointer_value
  IMPLICIT NONE
  INTEGER, DIMENSION(10), TARGET :: array= [1,3,5,7,9,11,13,15,17,19]
  INTEGER, dimension(2) :: array_fifth
  INTEGER, POINTER, DIMENSION(:) :: ptr_array => NULL()
  INTEGER, POINTER, DIMENSION(:) :: ptr_array_fifth => NULL()
  ptr_array => array
  array_fifth = every_fifth (ptr_array)
  if (any (array_fifth .ne. [1,11])) call abort
  if (any (every_fifth(ptr_array) .ne. [1,11])) call abort
CONTAINS
  FUNCTION every_fifth (ptr_array) RESULT (ptr_fifth)
    IMPLICIT NONE
    INTEGER, POINTER, DIMENSION(:) :: ptr_fifth
    INTEGER, POINTER, DIMENSION(:), INTENT(in) :: ptr_array
    INTEGER :: low
    INTEGER :: high
    low = LBOUND (ptr_array, 1)
    high = UBOUND (ptr_array, 1)
    ptr_fifth => ptr_array (low: high: 5) 
  END FUNCTION every_fifth
END PROGRAM test_pointer_value