[libcxx] Make sure use_system_cxx_lib does not override cxx_runtime_root for DYLD_LIBRARY_PATH
Otherwise, even specifying a runtime root different from the library
we're linking against won't work -- the library we're linking against
is always used. This is undesirable if we try testing something like
linking against a recent libc++.dylib but running the tests against an
older version (the back-deployment use case).
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@349171 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed
