[Bug libstdc++/58437] [4.7/4.8/4.9 Regression] Sorting value in reverse order is much slower compare to gcc44

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58437

--- Comment #8 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Thanks Chris. Note that, according at least to the Dup bug, some slow down is
noticeable in other less special cases too.