Get hhvm compiling with clang-3.5
Get hhvm compiling with clang-3.5

Summary:
This really wasn't that bad. A few mistaken uses of abs(), a few
functions unused except in debug mode, and some apparently-redundant
bool conversions.

@override-unit-failures

Test Plan: `fbconfig --clang --with-project-version=clang:dev` and tests

Reviewed By: meyering@fb.com

Subscribers: dcsommer, noamler, afrind, trunkagent, hphp-diffs@, ps, mathieubaudet, alandau, bmatheny, ptc, hphp-diffs@lists

FB internal diff: D1546566

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