fix test failure
fix test failure

Summary: zero out C data structure before use

Test Plan: run tests (for real this time), opt and dbg

Reviewed By: andrei.bajenov@fb.com

Subscribers: alandau, bmatheny

FB internal diff: D1355528

Tasks: 4422927

raphaelamorim/fbthrift,kangkot/fbthrift,project-zerus/fbthrift,SergeyMakarenko/fbthrift,HankFaan/fbthrift,getyourguide/fbthrift,kangkot/fbthrift,getyourguide/fbthrift,guker/fbthrift,maxwell-demon/fbthrift,getyourguide/fbthrift,getyourguide/fbthrift,maxwell-demon/fbthrift,uber/fbthrift,LinusU/fbthrift,raphaelamorim/fbthrift,getyourguide/fbthrift,LinusU/fbthrift,Orvid/fbthrift,fengshao0907/fbthrift,HankFaan/fbthrift,kangkot/fbthrift,chjp2046/fbthrift,project-zerus/fbthrift,guker/fbthrift,LinusU/fbthrift,sinjar666/fbthrift,soumith/fbthrift,fengshao0907/fbthrift,project-zerus/fbthrift,project-zerus/fbthrift,sinjar666/fbthrift,raphaelamorim/fbthrift,uber/fbthrift,soumith/fbthrift,sinjar666/fbthrift,jesboat/fbthrift,facebook/fbthrift,jesboat/fbthrift,jesboat/fbthrift,jesboat/fbthrift,Orvid/fbthrift,sinjar666/fbthrift,HankFaan/fbthrift,raphaelamorim/fbthrift,sinjar666/fbthrift,raphaelamorim/fbthrift,sinjar666/fbthrift,project-zerus/fbthrift,getyourguide/fbthrift,SergeyMakarenko/fbthrift,HankFaan/fbthrift,facebook/fbthrift,HankFaan/fbthrift,SergeyMakarenko/fbthrift,SergeyMakarenko/fbthrift,facebook/fbthrift,LinusU/fbthrift,fengshao0907/fbthrift,chjp2046/fbthrift,facebook/fbthrift,fengshao0907/fbthrift,soumith/fbthrift,Orvid/fbthrift,project-zerus/fbthrift,jesboat/fbthrift,SergeyMakarenko/fbthrift,maxwell-demon/fbthrift,uber/fbthrift,fengshao0907/fbthrift,fengshao0907/fbthrift,jesboat/fbthrift,guker/fbthrift,uber/fbthrift,soumith/fbthrift,HankFaan/fbthrift,jesboat/fbthrift,maxwell-demon/fbthrift,soumith/fbthrift,Orvid/fbthrift,soumith/fbthrift,LinusU/fbthrift,SergeyMakarenko/fbthrift,fengshao0907/fbthrift,Orvid/fbthrift,maxwell-demon/fbthrift,maxwell-demon/fbthrift,uber/fbthrift,uber/fbthrift,getyourguide/fbthrift,project-zerus/fbthrift,raphaelamorim/fbthrift,Orvid/fbthrift,guker/fbthrift,chjp2046/fbthrift,kangkot/fbthrift,raphaelamorim/fbthrift,fengshao0907/fbthrift,facebook/fbthrift,fengshao0907/fbthrift,chjp2046/fbthrift,facebook/fbthrift,Orvid/fbthrift,maxwell-demon/fbthrift,soumith/fbthrift,getyourguide/fbthrift,Orvid/fbthrift,project-zerus/fbthrift,chjp2046/fbthrift,kangkot/fbthrift,getyourguide/fbthrift,maxwell-demon/fbthrift,uber/fbthrift,facebook/fbthrift,SergeyMakarenko/fbthrift,jesboat/fbthrift,jesboat/fbthrift,HankFaan/fbthrift,getyourguide/fbthrift,chjp2046/fbthrift,SergeyMakarenko/fbthrift,SergeyMakarenko/fbthrift,uber/fbthrift,HankFaan/fbthrift,maxwell-demon/fbthrift,facebook/fbthrift,project-zerus/fbthrift,guker/fbthrift,guker/fbthrift,LinusU/fbthrift,sinjar666/fbthrift,jesboat/fbthrift,SergeyMakarenko/fbthrift,chjp2046/fbthrift,uber/fbthrift,raphaelamorim/fbthrift,kangkot/fbthrift,maxwell-demon/fbthrift,jesboat/fbthrift,kangkot/fbthrift,raphaelamorim/fbthrift,kangkot/fbthrift,HankFaan/fbthrift,Orvid/fbthrift,uber/fbthrift,getyourguide/fbthrift,uber/fbthrift,project-zerus/fbthrift,chjp2046/fbthrift,kangkot/fbthrift,raphaelamorim/fbthrift,chjp2046/fbthrift,jesboat/fbthrift,raphaelamorim/fbthrift,chjp2046/fbthrift,soumith/fbthrift,guker/fbthrift,LinusU/fbthrift,HankFaan/fbthrift,LinusU/fbthrift,HankFaan/fbthrift,project-zerus/fbthrift,soumith/fbthrift,SergeyMakarenko/fbthrift,guker/fbthrift,getyourguide/fbthrift,LinusU/fbthrift,guker/fbthrift,fengshao0907/fbthrift,fengshao0907/fbthrift,sinjar666/fbthrift,Orvid/fbthrift,maxwell-demon/fbthrift,guker/fbthrift,LinusU/fbthrift,project-zerus/fbthrift,Orvid/fbthrift,kangkot/fbthrift,sinjar666/fbthrift,sinjar666/fbthrift,uber/fbthrift,LinusU/fbthrift,guker/fbthrift,chjp2046/fbthrift,facebook/fbthrift,sinjar666/fbthrift,chjp2046/fbthrift,soumith/fbthrift,SergeyMakarenko/fbthrift,soumith/fbthrift,kangkot/fbthrift