[Bug c++/67844] New: Cannot make tuple of class with template constructor

[rbock at eudoxos dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67844

            Bug ID: 67844
           Summary: Cannot make tuple of class with template constructor
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rbock at eudoxos dot de
  Target Milestone: ---

Created attachment 36443
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36443&action=edit
struct with template constructor, instantiate, try to make_tuple from the
instance

If the constructor of a class is a template (see attached code), trying to call
make_tuple on an instance of this class fails to compile with g++-6.0.0.

The first error in the output is 

include/c++/6.0.0/type_traits:138:12: error: invalid use of incomplete type
‘struct std::is_convertible<const std::tuple<A>&, A>’

g++-4.9 as well as clang-3.[456] compile the code just fine.