diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index f3faeec..aaa73c1 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -3619,6 +3619,9 @@
 
   assert(Inputs.size() == 1 && "Unexpected number of inputs!");
 
+  // Silence warning about unused --serialize-diagnostics
+  Args.ClaimAllArgs(options::OPT__serialize_diags);
+
   types::ID InputType = Inputs[0].getType();
   const Arg *A;
   if ((A = Args.getLastArg(options::OPT_traditional)))