[Bug libfortran/40187] c_f_pointer with stride in SHAPE

[tkoenig at gcc dot gnu dot org]

------- Comment #4 from tkoenig at gcc dot gnu dot org  2009-05-19 17:17 -------
Created an attachment (id=17894)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17894&action=view)
Driver for failing test case (identical to c_f_pointer_shape_tests_2_driver.c)

$ gfortran c_f_pointer_shape_tests_4_driver.c c_f_pointer_shape_tests_4.f03
$ ./a.out
Aborted
$ gfortran -v
Using built-in specs.
Target: i686-pc-linux-gnu
Configured with: ../../../gcc/branches/fortran-dev/configure
--prefix=/home/ig25 --enable-languages=c,fortran --enable-maintainer-mode
Thread model: posix
gcc version 4.5.0 20090506 (experimental) (GCC)

The reason this fails is fairly obvious if you look at the code:  In
c_f_pointer_u0, there's

      for (i = 0; i < shapeSize; i++)
        {
          /* Lower bound is 1, as specified by the draft.  */
          f_ptr_out->dim[i].lbound = 1;
          /* Have to allow for the SHAPE array to be any valid kind for
             an INTEGER type.  */
#ifdef HAVE_GFC_INTEGER_1
          if (GFC_DESCRIPTOR_SIZE (shape) == 1)
            f_ptr_out->dim[i].ubound = ((GFC_INTEGER_1 *) (shape->data))[i];

which ignores the (sad) fact that shape could have a stride not equal
to one.  I found this when trying to convert this part to the array access
macros.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40187