implement basic support for __label__.  I wouldn't be shocked if there are
bugs from other clients that don't expect to see a LabelDecl in a DeclStmt,
but if so they should be easy to fix.

This implements most of PR3429 and rdar://8287027

llvm-svn: 125817
7 files changed
tree: 10a4fed274fe204f3b7c11910a663c60f9724795
  1. clang/
  2. compiler-rt/
  3. debuginfo-tests/
  4. libcxx/
  5. lldb/
  6. llvm/