[Bug libstdc++/54392] [4.7/4.8/4.9 Regression] std::string::assign() fails to update length

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54392

--- Comment #22 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So 5.0 material, given that we are not going to change std::string in 4.9?