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
with user code and that the boilerplate is counted towards the prologue.
<rdar://problem/18563763> Setting a breakpoint on "main" in a Swift program doesn't stop at user code
Swift SVN r22611