Add support for -rdynamic.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@118384 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 4d6cbf7..e28078d 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -3151,6 +3151,9 @@
     CmdArgs.push_back(A->getValue(Args));
   }
 
+  if (Args.hasArg(options::OPT_rdynamic))
+    CmdArgs.push_back("-export-dynamic");
+
   for (std::vector<std::string>::const_iterator i = ToolChain.ExtraOpts.begin(),
          e = ToolChain.ExtraOpts.end();
        i != e; ++i)