[Bug c++/86588] New: peculiar build issue using range-v3

["h2+bugs at fsfe dot org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86588

            Bug ID: 86588
           Summary: peculiar build issue using range-v3
           Product: gcc
           Version: 7.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: h2+bugs at fsfe dot org
  Target Milestone: ---

I have attached a code sample below and will provide an intermediate file that
shows that various forms of initialisation fail to build, while equivalent (at
least some) pass [all that are commented out fail, the last two are the only
that pass].

Since range-v3 pulls in a large amount of code the intermediate files are quite
large and I have as of yet been unsuccessful in reducing this to something that
still fails, but I hope someone with more expertise can track the compiler
while it tries/fails to deduce the type.

tested versions:
g++7 (FreeBSD Ports Collection) 7.3.1 20180712
g++8 (FreeBSD Ports Collection) 8.1.1 20180713

For reference also the issue at range-v3:
https://github.com/ericniebler/range-v3/issues/860


    std::string vec{"foo\nbar"};
    seqan3::detail::view_take_line v1(ranges::view::all(vec));

    assert("foo" == std::string(v1));
    assert(ranges::BidirectionalRange<decltype(v1)>());
    assert(ranges::View<decltype(v1)>());

//     auto v2 = v1 | ranges::view::reverse;                // #1

//     auto v2 = ranges::reverse_view<decltype(v1)>{v1};    // #2

    using t = ranges::reverse_view<decltype(v1)>;

//     auto v2 = t(v1);                                     // #3
//     auto v2 = t{v1};                                     // #3b

//     t v2 = t(v1);                                        // #4
//     t v2 = t{v1};                                        // #4b

//     t v2 = v1;                                           // #5

    t v2(v1);                                            // #6
    t v3{v1};                                            // #6b


    assert("oof" == std::string(v2));