* lto-symtab.c (lto_cgraph_replace_node): Do not call
	mark_reahcable_node.
	* cgraph.c (cgraph_remove_node): Do not clear reachable.
	(cgraph_mark_reachable_node): Remove.
	(cgraph_mark_force_output_node): Do not set reachable.
	(dump_cgraph_node): Do not dump reachable.
	(cgraph_create_virtual_clone): Do not set reachable.
	* cgraph.h (cgraph_node): Remove reachable flag.
	(varpool_node): Remove reachable flag.
	(cgraph_mark_if_needed): Remove.
	(cgraph_mark_reachable_node): Remove.
	* tree-emutls.c (ipa_lower_emutls): Do not check
	reachable.
	* cgraphunit.c (cgraph_finalize_function): Do not mark node as
	reachable.
	(cgraph_add_new_function): Likewise.
	(cgraph_mark_if_needed): Remove.
	(cgraph_analyze_function): Do not set target as reachable.
	(process_function_and_variable_attributes): Do not care about dllexport.
	(cgraph_analyze_functions): Do not set reachable flags.
	(cgraph_mark_functions_to_output): Do not check reachability.
	(cgraph_copy_node_for_versioning): Do not set reachable flag.
	(dbxout_expand_expr): Update.
	* c-decl.c (merge_decls): Do not track changed externs.
	* ipa.c: Include pointer-set.h
	(enqueue_cgraph_node): Use reachable pointer set.
	(process_references): Likewise.
	(cgraph_remove_unreachable_nodes): Likewise.
	(whole_program_function_and_variable_visibility): Do not recompute reachable.
	* trans-mem.c (ipa_tm_execute): Do not check reachable flag.

From-SVN: r186700