1 files changed, 5 insertions, 0 deletions
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index a2cf06a20cd..1cbb623824a 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -144,6 +144,11 @@ InputArgList *Driver::ParseArgStrings(ArrayRef<const char *> ArgList) {
     }
   }
 
+  for (arg_iterator it = Args->filtered_begin(options::OPT_UNKNOWN),
+         ie = Args->filtered_end(); it != ie; ++it) {
+    Diags.Report(diag::err_drv_unknown_argument) << (*it) ->getAsString(*Args);
+  }
+
   return Args;
 }