* lto-symtab.c (lto_symtab_merge_cgraph_nodes): Resolve cross module
	weakrefs.
	* cgraph.c (dump_cgraph_node): Do not ice on unresolved alias.
	* cgraphunit.c (handle_alias_pairs): Store target of unresolved weakrefs.
	(output_weakrefs): Update.

From-SVN: r199041