diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index e10c95c..5092915 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -610,6 +610,7 @@
            .Case("ownership_holds", true)
            .Case("ownership_returns", true)
            .Case("ownership_takes", true)
+           .Case("arc_cf_code_audited", true)
            // C1X features
            .Case("c_alignas", LangOpts.C1X)
            .Case("c_generic_selections", LangOpts.C1X)
diff --git a/test/SemaObjC/arc-cf.m b/test/SemaObjC/arc-cf.m
index b9a44d9..e7dcc22 100644
--- a/test/SemaObjC/arc-cf.m
+++ b/test/SemaObjC/arc-cf.m
@@ -1,5 +1,9 @@
 // RUN: %clang_cc1 -fsyntax-only -fobjc-arc -verify %s
 
+#if __has_feature(arc_cf_code_audited)
+char _global[-1]; // expected-error {{declared as an array with a negative size}}
+#endif
+
 typedef const void *CFTypeRef;
 typedef const struct __CFString *CFStringRef;