On Thu, Dec 19, 2019 at 12:40:12AM +0100, Jakub Jelinek wrote:
> Hi!
>
> While looking at PR92666, I've spotted a wrong-code issue where we ignore
> any side-effects on arguments passed to ellipsis if they have
> decltype(nullptr) type.
>
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
> trunk and release branches?
Looks fine to me, and reminds me of c++/90473.
> 2019-12-19 Jakub Jelinek <ja...@redhat.com>
>
> PR c++/92992
> * call.c (convert_arg_to_ellipsis): For decltype(nullptr) arguments
> that have side-effects use cp_build_compound_expr.
>
> * g++.dg/cpp0x/nullptr45.C: New test.
>
> --- gcc/cp/call.c.jj 2019-12-17 10:19:51.013282361 +0100
> +++ gcc/cp/call.c 2019-12-18 18:23:01.441357443 +0100
> @@ -7822,7 +7822,12 @@ convert_arg_to_ellipsis (tree arg, tsubs
> arg = convert_to_real_nofold (double_type_node, arg);
> }
> else if (NULLPTR_TYPE_P (arg_type))
> - arg = null_pointer_node;
> + {
> + if (TREE_SIDE_EFFECTS (arg))
> + arg = cp_build_compound_expr (arg, null_pointer_node, complain);
> + else
> + arg = null_pointer_node;
> + }
FWIW, I was wondering if this should be nullptr_node instead but
http://eel.is/c++draft/expr.call#12.sentence-5 says "An argument that has
type cv std::nullptr_t is converted to type void*." Perhaps there should
be a comment to that effect...
--
Marek Polacek • Red Hat, Inc. • 300 A St, Boston, MA
