* linux-nat.h (linux_proc_get_tgid): Declare.

	* linux-nat.h (linux_proc_get_tgid): Declare.
	* linux-nat.c (linux_proc_get_tgid): New.
	* linux-thread-db.c (struct thread_db_info): New field
	`need_stale_parent_threads_check'.
	(add_thread_db_info): Set it.
	(find_new_threads_callback): Ignore stale fork parent threads.
	(thread_db_resume): New.
	(init_thread_db_ops): Install thread_db_resume.