https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93106
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |mpolacek at gcc dot gnu.org
--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
(In reply to Jason Merrill from comment #3)
> Confirmed. check_return_expr can't use convert_for_initialization to test
> whether to treat the returned lvalue as an rvalue.
Indeed: convert_for_initialization -> perform_implicit_conversion_flags ->
convert_like_real will build_temp for the rvalue version of OBJ, so it calls
build_special_member_call -> build_new_method_call_1.
Here we have three candidates:
X::X(X&&)
constexpr X::X(const X&)
constexpr X::X()
the last one is not viable so splice_viable kills it. And tourney selects
X::X(X&&)
as expected. But we pass it to build_over_call and that will not complain and
just return error_mark_node for a DECL_DELETED_FN function. Then the second
stage of the two-stage overload resolution succeeds. I guess we need to stop
and issue an error when we found a move ctor, but it's deleted (but not if we
don't find a move ctor at all).
(Came here in the context of PR91212 where this convert_for_initialization
selects the wrong overload.)
