tree 28c259988623edcf692e8d6ae3030ef4209d11f3
parent 80a7c2ab824381cd72e772c5af863cbda17f0111
author Dan Willemsen <dwillemsen@google.com> 1450152164 -0800
committer Dan Willemsen <dwillemsen@google.com> 1450828381 -0800

Use xcrun and xcode-select to auto-configure mac sdk

This roughly matches what make uses, but with less string parsing.
Also use a full path to "ar", so that we can depend on it.

Change-Id: I5e9d4c06b6cbbbfbf93e563dace128943db21b02