Driver: Support -fno-lto.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129712 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index a3c93bd..39ace11 100644
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -950,7 +950,8 @@
     } else if (Args.hasArg(options::OPT_emit_ast)) {
       return new CompileJobAction(Input, types::TY_AST);
     } else if (Args.hasArg(options::OPT_emit_llvm) ||
-               Args.hasArg(options::OPT_flto) || HasO4) {
+               Args.hasFlag(options::OPT_flto, options::OPT_fno_lto, false) ||
+               HasO4) {
       types::ID Output =
         Args.hasArg(options::OPT_S) ? types::TY_LTO_IR : types::TY_LTO_BC;
       return new CompileJobAction(Input, Output);