Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
The former is for debugging, the latter is for detailed presentation to users.
swift -print-ast will continue using printEverything, as will swift-ide-test,
but all other features should use printVerbose.
Swift SVN r20432