For compiling codes required for macro support, we now need swiftc
compiler in the build machine.
Unlike Darwin OSes, where swiftCore runtime is guaranteed to be present
in /usr/lib, Linux doesn't have ABI stability and the stdlib of the
build machine is not at the specific location. So the built compiler
cannot relies on the shared object in the toolchain.
LIT runs each unittest once to enumerate all tests. When the test
executable crashes during this run, no tests will be found and all
tests in that executable will be skipped. The SwiftDemangleTests
executable depends on a shared library. This patch changes the LIT
configuration to set the shared library path to the lib directory in
the build artifacts and thus re-enables the SwiftDemangleTests unit
test.
This library becomes a permanent interface that we would need to support
in the long term, so we should get dylib names and APIs right.
rdar://20418214
Swift SVN r26957
