https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85868
--- Comment #6 from Harald Anlauf <anlauf at gmx dot de> ---
Another testcase suitable for debugging is the following, which better
shows correspondence for pre-F2008 and F2008+ variants:
program test
implicit none
integer, pointer :: t(:), u(:)
integer :: i
allocate (t(-1:5))
do i = -1, 5
t(i) = i
end do
call p (t ) ! Pointer with lower bound = -1 from allocation
u => t ! Pointer assignment sets same lower bound
call p (u)
!
u => t( :) ! Pointer assignment with implicit lower bound (1)
call p (u)
call p (t( :)) ! Full array, behaves the same
!
call p (t( 0:)) ! Array section
u => t(0:) ! Pointer assignment with implicit lower bound (1)
call p (u)
u(0:) => t(0:) ! Pointer assignment with given lower bound (0)
call p (u)
contains
subroutine p (a)
integer, pointer, intent(in) :: a(:)
print *, a(1)
end subroutine p
end program
NAG and Crayftn both print the supposedly correct result:
1
1
-1
-1
0
0
1
Current 9-trunk:
1
1
-1
1
2
0
1
gcc-8.2.1:
1
1
-1
1
0
0
1
gcc-7.3.1, 6.x, 5.x, 4.6:
1
1
-1
1
1
0
1
gcc-4.9, 4.8:
1
1
-1
1
1
0
0
So it is a varying sort of wrong code issue...
Only output lines 1,2,3 and 6 are always correct.
