Merge pull request #7653 from pengli:deriv
authorAlexander Alekhin <alexander.a.alekhin@gmail.com>
Mon, 14 Nov 2016 13:40:04 +0000 (13:40 +0000)
committerAlexander Alekhin <alexander.a.alekhin@gmail.com>
Mon, 14 Nov 2016 13:40:04 +0000 (13:40 +0000)

Trivial merge