Support -fatal-warnings for the assembler frontend


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@131662 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/driver/cc1as_main.cpp b/tools/driver/cc1as_main.cpp
index ec6ce65..f449235 100644
--- a/tools/driver/cc1as_main.cpp
+++ b/tools/driver/cc1as_main.cpp
@@ -172,6 +172,8 @@
     }
   }
   Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
+  if (Args->hasArg(OPT_fatal_warnings))
+    Opts.LLVMArgs.push_back("-fatal-assembler-warnings");
   Opts.OutputPath = Args->getLastArgValue(OPT_o);
   if (Arg *A = Args->getLastArg(OPT_filetype)) {
     StringRef Name = A->getValue(*Args);