[Bug fortran/40962] New: [4.5.0,4.4.0,4.3.2] conversion problem for f-allocatable -> cptr -> fptr -> f-allocatable

["reuter at physik dot uni-freiburg dot de" <gcc-bugzilla at gcc dot gnu dot org>]

The following test code below (which works with the NAG 5.2 Fortran Compiler) 
seems to choke over the conversion f-allocatable -> cptr -> fptr ->
f-allocatable. With NAG the output should be:
--------------------------------------------------
nagfor tab3.f90 -o tab3 && ./tab3
NAG Fortran Compiler Release 5.2(686)
[NAG Fortran Compiler normal termination]
In:   1  2  3  4  5  6 -1 -2 -3 -4 -5 -6
Tmp:  1  2  3  4  5  6 -1 -2 -3 -4 -5 -6
Out:  1  2  3  4  5  6 -1 -2 -3 -4 -5 -6
-------------------------------------------------


For gfortran 4.5.0 the result is:
In:   1  2  3  4  5  6 -1 -2 -3 -4 -5 -6
Tmp:  1  2  3 -1 -2 -3 -1 -2 -3 -4 -5 -6
Out:  1  2  3 -1 -2 -3 -4 -5 -6  0  0  0


while for gfortran 4.3.2 the result is:
-------------------------------------------------
In:   1  2  3  4  5  6 -1 -2 -3 -4 -5 -6
Tmp:  1  2  3 -1 -2 -3 -1 -2 -3 -4 -5 -6
Out:  1  2  3 -1 -2 -3 -4 -5 -6 ** **  0

It looks as if the order of indices gets confused by gfortran in changing the
corresponding pointers. According to the F2003 Handbook this code should be
allowed. 


TEST PROGRAM:


----------------------------------------------------------
program main

   use iso_c_binding
   implicit none

   character(*), parameter :: fmt = "(A,40(1x,I2))"

   integer, parameter :: n1 = 2
   integer, parameter :: n2 = 3
   integer, parameter :: n3 = 2

   integer, dimension(2), parameter :: shape2 = (/ n1, n2 /)
   integer, dimension(3), parameter :: shape3 = (/ n1, n2, n3 /)

   integer, dimension(n1, n2), parameter :: &
     c0001 = reshape ( (/  1, 2,  3, 4,  5, 6 /), shape2)
   integer, dimension(n1, n2), parameter :: &
     c0002 = reshape ( (/ -1,-2, -3,-4, -5,-6 /), shape2)
   integer, dimension(n1, n2, n3), parameter :: &
     table_in = reshape ( (/ c0001, c0002 /), shape3)

   integer, dimension(:,:,:), allocatable, target :: table_out

   print fmt, "In: ", table_in

   ! Allocate table_out with shape=shape3
   allocate (table_out (n1, n2, n3))

   ! Set table_out via a C pointer
   call set_table (c_loc (table_out))

   print fmt, "Out:", table_out

contains

   subroutine set_table (cptr)

     type(c_ptr), intent(in) :: cptr
     integer, dimension(:,:,:), pointer :: table_tmp

     ! This should make table_tmp an alias to table_out
     call c_f_pointer (cptr, table_tmp, shape3)

     ! Now set the value of table_tmp
     table_tmp = table_in

     print fmt, "Tmp:", table_tmp

   end subroutine set_table

end program main
--------------------------------------------------


-- 
           Summary: [4.5.0,4.4.0,4.3.2] conversion problem for  f-
                    allocatable -> cptr -> fptr -> f-allocatable
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reuter at physik dot uni-freiburg dot de
 GCC build triplet: 4.5.0 Ref. svn r
  GCC host triplet: Linux 32bit, 64bit, MAC OS X
GCC target triplet: gcc, gfortran 4.3.2, 4.4.0, 4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40962