diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index b637938..819ed4b 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -793,6 +793,8 @@
     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Subscripting;
   if (Args.hasArg(OPT_objcmt_migrate_property))
     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Property;
+  if (Args.hasArg(OPT_objcmt_migrate_readonly_property))
+    Opts.ObjCMTAction |= FrontendOptions::ObjCMT_ReadonlyProperty;
 
   if (Opts.ARCMTAction != FrontendOptions::ARCMT_None &&
       Opts.ObjCMTAction != FrontendOptions::ObjCMT_None) {