The objc package adds a parser that uses the clang -cc1 -ast-dump command to extract type information about ObjC classes and protocol. The resulting type information is needed to generate ObjC API wrappers in Go. This is the first part of the implementation of proposal golang/go#17102. For golang/go#17102 Change-Id: I8382b54c0bd315703ec5a62cc177e1a2ace061e9 Reviewed-on: https://go-review.googlesource.com/29173 Reviewed-by: David Crawshaw <crawshaw@golang.org>