3 files changed, 9 insertions, 0 deletions
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 14c87d8216..e125ab78f4 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -1019,6 +1019,10 @@ bool Darwin::SupportsObjCGC() const {
   return !isTargetIPhoneOS();
 }
 
+bool Darwin::SupportsObjCARC() const {
+  return isTargetIPhoneOS() || !isMacosxVersionLT(10, 6);
+}
+
 std::string
 Darwin_Generic_GCC::ComputeEffectiveClangTriple(const ArgList &Args,
                                                 types::ID InputType) const {
diff --git a/lib/Driver/ToolChains.h b/lib/Driver/ToolChains.h
index 0fb213828f..0d591107de 100644
--- a/lib/Driver/ToolChains.h
+++ b/lib/Driver/ToolChains.h
@@ -379,6 +379,8 @@ public:
 
   virtual bool SupportsObjCGC() const;
 
+  virtual bool SupportsObjCARC() const;
+
   virtual bool UseDwarfDebugFlags() const;
 
   virtual bool UseSjLjExceptions() const;
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 14fb9cb718..c5caaf024f 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -2225,6 +2225,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // NOTE: This logic is duplicated in ToolChains.cpp.
   bool ARC = isObjCAutoRefCount(Args);
   if (ARC) {
+    if (!getToolChain().SupportsObjCARC())
+      D.Diag(diag::err_arc_unsupported);
+
     CmdArgs.push_back("-fobjc-arc");
 
     // FIXME: It seems like this entire block, and several around it should be