diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index db9d397..4cb73db 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -290,7 +290,7 @@
     if (A->getValue(Args)[0] == '\0')
       CmdArgs.push_back("-O1");
     else
-      CmdArgs.push_back(A->getValue(Args));
+      A->render(Args, CmdArgs);
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_clang_W_Group, options::OPT_pedantic_Group);