[PATCH] Add EXPERIMENTAL --rtlib=compiler-rt to GNU Clang

[Alexey Samsonov]

  Using --rtlib on Linux looks reasonable to me, but probably you should ask for other opinions.

  Could you please add tests for this and upload the full context to phab in future revisions.


================
Comment at: lib/Driver/Tools.cpp:6708
@@ +6707,3 @@
+
+      switch(RLT) {
+      case ToolChain::RLT_CompilerRT:
----------------
This logic (choosing between addClangRTLinux and AddLibgcc) should probably be factored into separate function, as it's duplicated below.


http://llvm-reviews.chandlerc.com/D2740