B2G device builds are currently broken on Mac on both trunk and b2g18: bug 834867 and bug 834859. A significant number of our devs build on Mac. It's therefore critical that B2G device builds work there as well. These bugs are evidence that builds can fail on Mac while they succeed on Linux. To be clear, we need this on m-c, m-i, try, and b2g18. Can you guys please add a builder to tinderbox for this configuration? It would be great if you could run some tests, e.g. to ensure that the resultant builds start up. But if resources are a constraint, I don't think you need to run all the tests.
We've had these for awhile: http://ftp.mozilla.org/pub/mozilla.org/b2g/nightly/latest-mozilla-central/