Re: [Patch, fortran] PR24276 Components of a derived type array not passed as an array

[Tobias dot Schlueter at Physik dot Uni-Muenchen dot DE]

Hi Paul,

sorry for taking so long.  The patch is not yet ok, see below.  (Sorry, that I'm
not correctly following up in the thread.)

> + /* Returns a reference to a temporary array into which a component of
> +    an actual argument derived type array is copied and then returned
> +    after the function call.
> +    TODO Get rid of this kludge, when array descriptors are capable of
> +    handling aliassed arrays.  */

'aliased' instead of 'aliassed', but since 'aliasing' means something different,
(namely, two symbols pointing to the same memory location), maybe an altogether
different word would be appropriate?

+   for (n = info->dimen - 1 ;n >= 0 ;n--)

Exchange semicolons and blanks.

> +     {
> +       if (n > 0)
> +         {
> + 	  tree tmp_str;
> + 	  tmp = rse.loop->loopvar[n];
> + 	  tmp = fold_build2 (MINUS_EXPR, gfc_array_index_type,
> + 			     tmp, rse.loop->from[n]);
> + 	  tmp = fold_build2 (PLUS_EXPR, gfc_array_index_type,
> + 			     tmp, tmp_index);
> +
> + 	  tmp_str = fold_build2 (MINUS_EXPR, gfc_array_index_type,
> + 				 rse.loop->to[n-1], rse.loop->from[n-1]);
> + 	  tmp_str = fold_build2 (PLUS_EXPR, gfc_array_index_type,
> + 				 tmp_str, gfc_index_one_node);
> +
> + 	  tmp_index = fold_build2 (MULT_EXPR, gfc_array_index_type,
> + 				   tmp, tmp_str);
> + 	}
> +       else
> + 	{
> + 	  tmp_index = fold_build2 (MINUS_EXPR, gfc_array_index_type,
> + 				   tmp_index, rse.loop->from[n]);
> + 	  gfc_add_modify_expr (&rse.loop->code[n], offset, tmp_index);
> +
> + 	  tmp_index = fold_build2 (PLUS_EXPR, gfc_array_index_type,
> + 				   rse.loop->loopvar[n], offset);
> + 	}
> +     }

You're not using the tmp_index built for n > 1 anywhere.  You should pull the
else branch out of the loop, and change the termination condition to n > 0. 
I'm not sure if the not-using of the tmp_index' is an error, otherwise you
could completely do away with the loop.

Thank you,
- Tobi