PR middle-end/20622
	* cgraph.h (struct cgraph_varpool_node): Add alias field.
	* cgraph.c (cgraph_varpool_assemble_pending_decls): Don't call
	assemble_variable on aliases.
	* varasm.c (assemble_alias): Set node->alias.
	* toplev.c (wrapup_global_declarations): Don't call
	rest_of_decl_compilation on aliases again.

	* gcc.dg/alias-7.c: New test.

From-SVN: r97161