Inconsistent output on Linux

[Mahesh Pittala]

build info: 16bpp, gcc command: RaceHorses_416x240_30_10bit.yuv --preset=veryfast --max-tu-size 8 -f50 --hash=1 --no-info --psnr --ssim --input-depth 10 --input-res 416x240 --fps 30

It is hard to reproduce, have to run 20-30 times

[Deepthi Nandakumar]

with 9574b4cc645b and 9fd212de2469