[Bug libstdc++/77395] [6/7 Regression] std::is_constructible is false for type constructible via implicit conversion operator affecting std::tuple

[ville at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77395

--- Comment #7 from ville at gcc dot gnu.org ---
Author: ville
Date: Wed Aug 31 12:38:05 2016
New Revision: 239890

URL: https://gcc.gnu.org/viewcvs?rev=239890&root=gcc&view=rev
Log:
        PR libstdc++/77395
        * include/std/type_traits (is_constructible): Forward-declare...
        (__is_base_to_derived_ref): ...and use here.
        * testsuite/20_util/declval/requirements/1_neg.cc: Adjust.
        * testsuite/20_util/is_constructible/77395.cc: New.
        * testsuite/20_util/make_signed/requirements/typedefs_neg.cc: Adjust.
        * testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc:
        Likewise.
        * testsuite/20_util/tuple/77395.cc: New.

Added:
   
branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/is_constructible/77395.cc
      - copied, changed from r239884,
branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
    branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/tuple/77395.cc
      - copied, changed from r239884,
branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
Modified:
    branches/gcc-6-branch/libstdc++-v3/ChangeLog
    branches/gcc-6-branch/libstdc++-v3/include/std/type_traits
   
branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/declval/requirements/1_neg.cc
   
branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc
   
branches/gcc-6-branch/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc