Rollup of 8 pull requests#68113

Closed

Centril wants to merge 46 commits intorust-lang:masterfrom

Centril:rollup-kx49om9

Commits on Jan 9, 2020

Label unmarked time
Zoxc
committed
Tweak timers
Zoxc
committed
Add llvm-skip-rebuild to opts
Matthew Healy
committed

Commits on Jan 10, 2020

Commits on Jan 11, 2020