This is the Linux equivalent of 3731a2ff0. There's probably a way to
merge them into one file cleanly, but the extra linker args on OS X
make it a little tricky. I'm deciding not to worry about it right now.
...when interpreting. Otherwise, the script may depend on library X, which
depends on library Y, where library Y is a standard Swift library, located
in lib/swift/$PLATFORM/.
Finishes rdar://problem/23588774
...as described in rdar://problem/23588774. We don't really have a good way
to make this test cross-platform as such, but I'll add a Linux version soon.
