[beta] Backport #48252#48340

Merged

bors merged 3 commits intorust-lang:betafrom

Mark-Simulacrum:beta-next

Feb 19, 2018

Commits on Feb 18, 2018

Prevent silently ignoring unmatched paths
Mark-Simulacrum
committed
Consider paths passed to x.py to be root-relative.
Mark-Simulacrum
committed
Fix panic when `x.py` is called without any arguments.

kennytm
authored and
Mark-Simulacrum
committed