2 files changed, 13 insertions, 0 deletions
diff --git a/clang/lib/Driver/ToolChains.h b/clang/lib/Driver/ToolChains.h
index 04288a2ee06..33b80534532 100644
--- a/clang/lib/Driver/ToolChains.h
+++ b/clang/lib/Driver/ToolChains.h
@@ -176,6 +176,12 @@ public:
             getTriple().getArch() == llvm::Triple::x86_64);
 #endif
   }
+  
+  virtual bool IsObjCDefaultSynthPropertiesDefault() const {
+    // Always allow default synthesized properties on Darwin.
+    return true;
+  }
+
   virtual bool IsObjCNonFragileABIDefault() const {
     // Non-fragile ABI is default for everything but i386.
     return getTriple().getArch() != llvm::Triple::x86;
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 9df276d9c24..cee00edd2df 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -1484,6 +1484,13 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
           CmdArgs.push_back("-fobjc-dispatch-method=non-legacy");
       }
     }
+    
+    // -fobjc-default-synthesize-properties=0 is default.
+    if (Args.hasFlag(options::OPT_fobjc_default_synthesize_properties,
+                     options::OPT_fno_objc_default_synthesize_properties,
+                     getToolChain().IsObjCDefaultSynthPropertiesDefault())) {
+      CmdArgs.push_back("-fobjc-default-synthesize-properties");
+    }
   }
 
   if (!Args.hasFlag(options::OPT_fassume_sane_operator_new,