Fix test when using an installed libc++

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@285392 91177308-0d34-0410-b5e6-96231b3b80d8

test/libcxx/test/config.py

@@ -290,6 +290,7 @@ class Configuration(object):
         # XFAIL markers for tests that are known to fail with versions of
         # libc++ as were shipped with a particular triple.
         if self.use_system_cxx_lib:
+            self.config.available_features.add('with_system_cxx_lib')
             self.config.available_features.add(
                 'with_system_cxx_lib=%s' % self.config.target_triple)
 

test/libcxx/version.pass.cpp

@@ -8,6 +8,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: with_system_cxx_lib
+
 // Test the _LIBCPP_VERSION and _LIBCPP_LIBRARY_VERSION macros
 
 #include <__config>