[PATCH] Emit DWARF info for all code section in an assembly file

[Oliver Stannard]

  > Let's split the testcase generalization out

  Done, see new dependency

  > I really don't want to add -gdwarf-N to llvm-mc

  Why is that? I understand that we don't _have_ to maintain compatibility with clang, but I can't see a good reason not to. This way, the same options are accepted for the common cases (zero or one uses of -gdwarf-N), and an understandable error is thrown in the more complex case of multiple uses or it.

  > Seems sad. I guess that can be a refactor. (EmitIntValue -> EmitInt16)

  Yes, but that would be a separate patch.

http://llvm-reviews.chandlerc.com/D2697