diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index e93e642..b7357ec 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -517,6 +517,8 @@
   Args.AddLastArg(CmdArgs, options::OPT_fvisibility_EQ);
   Args.AddLastArg(CmdArgs, options::OPT_fwritable_strings);
 
+  Args.AddLastArg(CmdArgs, options::OPT_pthread);
+
   // Forward stack protector flags.
   if (Arg *A = Args.getLastArg(options::OPT_fno_stack_protector,
                                options::OPT_fstack_protector_all,