https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70845
Bug ID: 70845
Summary: inherited piecewise_construct_t constructor from
std::pair by "using-declarations" is missing
Product: gcc
Version: 6.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: tuwwcn at gmail dot com
Target Milestone: ---
This code is PASSED by gcc 5.3.0, but REJECTED by 6.1.0.(all using --std=c++14)
---------------------------
code is like this:
struct Test : public std::pair<int, std::string> {
using std::pair<int, std::string>::pair;
};
Test p(std::piecewise_construct, std::forward_as_tuple(1),
std::forward_as_tuple("abcd"));
---------------------------
Error messages produced by gcc 6.1.0 is:
error: use of deleted function ‘constexpr std::tuple< <template-parameter-1-1>
>::tuple(const std::tuple< <template-parameter-1-1> >&) [with _Elements =
{int&&}]’
using std::pair<int, std::string>::pair;
gcc-6.1.0/include/c++/6.1.0/tuple:633:17: note: ‘constexpr std::tuple<
<template-parameter-1-1> >::tuple(const std::tuple< <template-parameter-1-1>
>&) [with _Elements = {int&&}]’ is implicitly deleted because the default
definition would be ill-formed:
constexpr tuple(const tuple&) = default;
^~~~~
gcc-6.1.0/include/c++/6.1.0/tuple:633:17: error: use of deleted function
‘constexpr std::_Tuple_impl<_Idx, _Head>::_Tuple_impl(const
std::_Tuple_impl<_Idx, _Head>&) [with long unsigned int _Idx = 0ul; _Head =
int&&]’
gcc-6.1.0/include/c++/6.1.0/tuple:363:17: note: ‘constexpr
std::_Tuple_impl<_Idx, _Head>::_Tuple_impl(const std::_Tuple_impl<_Idx,
_Head>&) [with long unsigned int _Idx = 0ul; _Head = int&&]’ is implicitly
deleted because the default definition would be ill-formed:
constexpr _Tuple_impl(const _Tuple_impl&) = default;
^~~~~~~~~~~
gcc-6.1.0/include/c++/6.1.0/tuple:363:17: error: use of deleted function
‘constexpr std::_Head_base<_Idx, _Head, false>::_Head_base(const
std::_Head_base<_Idx, _Head, false>&) [with long unsigned int _Idx = 0ul; _Head
= int&&]’
gcc-6.1.0/include/c++/6.1.0/tuple:110:17: note: ‘constexpr
std::_Head_base<_Idx, _Head, false>::_Head_base(const std::_Head_base<_Idx,
_Head, false>&) [with long unsigned int _Idx = 0ul; _Head = int&&]’ is
implicitly deleted because the default definition would be ill-formed:
constexpr _Head_base(const _Head_base&) = default;
^~~~~~~~~~
gcc-6.1.0/include/c++/6.1.0/tuple:110:17: error: copying non-static data member
‘int&& std::_Head_base<0ul, int&&, false>::_M_head_impl’ of rvalue reference
type
