[Bug libstdc++/78939] [C++17] interferes with structured binding from struct

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78939

--- Comment #14 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Fri May 12 14:43:11 2017
New Revision: 247973

URL: https://gcc.gnu.org/viewcvs?rev=247973&root=gcc&view=rev
Log:
PR libstdc++/78939 make tuple_size<cv T> depend on tuple_size<T>

        PR libstdc++/78939
        * include/std/utility (tuple_size<cv T>): Only define partial
        specializations when tuple_size<T>::value is valid.
        * testsuite/20_util/tuple/78939.cc: New.
        * testsuite/20_util/tuple/cv_tuple_size_neg.cc: New.

Added:
    trunk/libstdc++-v3/testsuite/20_util/tuple/78939.cc
    trunk/libstdc++-v3/testsuite/20_util/tuple/cv_tuple_size_neg.cc
Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/std/utility