[Bug go/83102] [8 Regression] go bootstrap error in ast-dump.cc due to __is_invocable failure

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83102

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Wed Nov 22 11:06:15 2017
New Revision: 255052

URL: https://gcc.gnu.org/viewcvs?rev=255052&root=gcc&view=rev
Log:
PR go/83102 relax std::set checks for invocable comparison object

        PR go/83102
        * include/bits/stl_tree.h (_Rb_tree): Relax invocable checks for
        comparison object pre-C++17.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/bits/stl_tree.h