[Bug libstdc++/50871] [C++0x] G++ fails to reject explicitly-defaulted function definition with different exception spec in system headers

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50871

--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-12-03 15:34:53 UTC ---
It occurs to me we could use a diagnostic pragma to disable warnings about
variadic templates in our headers, instead of marking them as system headers.
That wouldn't work currently because the variadic templates warning is [enabled
by default] so there's no option to disable it.