message: [Swift] Silence false positives in ASAN.
  <rdar://problem/50644029>
diff: @@ -35,6 +35,12 @@ config.test_source_root = os.path.dirname(__file__)
  # test_exec_root: The root path where tests should be run.
  config.test_exec_root = os.path.join(config.lldb_obj_root, 'lit')
  +# Begin Swift mod.
  +# Swift's libReflection builds without ASAN, which causes a known
  +# false positive in std::vector. If sanitizers are off, this is just
  +# a no-op
  +config.environment['ASAN_OPTIONS'] = 'detect_container_overflow=0'
  +# End Swift mod.
  llvm_config.use_default_substitutions()
  