Index: lib/Driver/ToolChains/Clang.cpp
===================================================================
--- lib/Driver/ToolChains/Clang.cpp
+++ lib/Driver/ToolChains/Clang.cpp
@@ -980,6 +980,7 @@
         DepTarget = Args.MakeArgString(llvm::sys::path::filename(P));
       }
 
+      CmdArgs.push_back("-w");
       CmdArgs.push_back("-MT");
       SmallString<128> Quoted;
       QuoteTarget(DepTarget, Quoted);