[Patch, Fortran] PR 41714: [OOP] ALLOCATE SOURCE= does not properly copy the value from SOURCE

[Richard Guenther]

On Sun, Oct 25, 2009 at 3:52 PM, Paul Richard Thomas
<paul.richard.thomas@gmail.com> wrote:
> Janus,
>
> It looks OK to me except:
>
>>        PR fortran/41714
>>        * trans-expr.c (gfc_build_memcpy_call): Take care of the case that the
>>        call to '__builtin_memcpy' is optimized away (replaced by a direct
>>        assignment).
>
> How the heck does that work?  It comes out as a NOP_EXPR and yet it's
> really an assignment..... Is that documented somewhere?

That patch looks indeed dubious.  It tests for an implementation detail
(the memcpy folder returns (void *) ({ *dst = *src; dst; })).  You should
be able to unconditionally fold-convert to void_type_node as in the
original code.  Instead tree_annotate_all_with_location should be fixed.

Richard.