On Tue, May 24, 2022 at 08:36:39AM -0400, Jason Merrill wrote:
> On 5/16/22 11:36, Marek Polacek wrote:
> > +static tree
> > +replace_placeholders_for_class_temp_r (tree *tp, int *, void *data)
> > +{
> > + tree t = *tp;
> > + tree full_expr = *static_cast<tree *>(data);
> > +
> > + /* We're looking for a TARGET_EXPR nested in the whole expression. */
> > + if (TREE_CODE (t) == TARGET_EXPR
> > + && !potential_prvalue_result_of (t, full_expr))
> > + {
> > + tree init = TARGET_EXPR_INITIAL (t);
> > + while (TREE_CODE (init) == COMPOUND_EXPR)
> > + init = TREE_OPERAND (init, 1);
>
> Hmm, how do we get a COMPOUND_EXPR around a CONSTRUCTOR?
Sadly, that's possible for code like (from nsdmi-aggr18.C)
struct D {
int x = 42;
B b = (true, A{x});
};
where the TARGET_EXPR_INITIAL is
<<< Unknown tree: void_cst >>>, {.x=((struct D *) this)->x,
.y=(&<PLACEHOLDER_EXPR struct A>)->x}
Marek
