Re-XFAIL UBSan vptr testcase on darwin.

Partial revert of r235961; the test still fails on Green Dragon bots.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@236135 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/ubsan/TestCases/TypeCheck/vptr.cpp b/test/ubsan/TestCases/TypeCheck/vptr.cpp
index 38ecf75..bb2c649 100644
--- a/test/ubsan/TestCases/TypeCheck/vptr.cpp
+++ b/test/ubsan/TestCases/TypeCheck/vptr.cpp
@@ -23,6 +23,8 @@
 // RUN: echo "vptr_check:S" > %t.loc-supp
 // RUN: UBSAN_OPTIONS="suppressions='%t.loc-supp':halt_on_error=1" not %run %t x- 2>&1 | FileCheck %s --check-prefix=CHECK-LOC-SUPPRESS
 
+// FIXME: This test doesn't pass on Darwin yet.
+// XFAIL: darwin
 // REQUIRES: stable-runtime
 #include <new>