| //===----------------------------------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // UNSUPPORTED: c++98, c++03 |
| |
| // <tuple> |
| |
| // template <class... Types> class tuple; |
| |
| // template <class Alloc> tuple(allocator_arg_t, Alloc const&) |
| |
| // Libc++ has to deduce the 'allocator_arg_t' parameter for this constructor |
| // as 'AllocArgT'. Previously libc++ has tried to support tags derived from |
| // 'allocator_arg_t' by using 'is_base_of<AllocArgT, allocator_arg_t>'. |
| // However this breaks whenever a 2-tuple contains a reference to an incomplete |
| // type as its first parameter. See PR27684. |
| |
| #include <tuple> |
| #include <cassert> |
| |
| struct IncompleteType; |
| extern IncompleteType inc1; |
| extern IncompleteType inc2; |
| IncompleteType const& cinc1 = inc1; |
| IncompleteType const& cinc2 = inc2; |
| |
| int main() { |
| using IT = IncompleteType; |
| { // try calling tuple(Tp const&...) |
| using Tup = std::tuple<const IT&, const IT&>; |
| Tup t(cinc1, cinc2); |
| assert(&std::get<0>(t) == &inc1); |
| assert(&std::get<1>(t) == &inc2); |
| } |
| { // try calling tuple(Up&&...) |
| using Tup = std::tuple<const IT&, const IT&>; |
| Tup t(inc1, inc2); |
| assert(&std::get<0>(t) == &inc1); |
| assert(&std::get<1>(t) == &inc2); |
| } |
| } |
| |
| struct IncompleteType {}; |
| IncompleteType inc1; |
| IncompleteType inc2; |