https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119
--- Comment #20 from Marek Polacek <mpolacek at gcc dot gnu.org> --- Sorry, the patch hasn't been applied to 4.9 nor 4.8 branch yet, and I don't think it should be backported as-is, because just today I found out that the patch contains a bug; see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64709
