Update libc and some fixes for x86_64-unknown-linux-gnux32#45391

Merged

bors merged 2 commits intorust-lang:masterfrom

Oct 21, 2017

Commits on Oct 19, 2017

Update libc to include linux gnux32 fixes
malbarbo
committed

Commits on Oct 20, 2017

Fix some tests for linux gnux32
malbarbo
committed