PR c++/67354
	* cp-tree.h (defer_mangling_aliases): Declare.
	(generate_mangling_aliases): New prototype.
	* decl2.c (defer_mangling_aliases): New variable.
	(note_mangling_alias): Use !defer_mangling_aliases
	instead of at_eof.
	(generate_mangling_aliases): No longer static. Clear
	defer_mangling_aliases.
	* optimize.c (maybe_thunk_body): Defer emitting mangling aliases
	if !defer_mangling_aliases until the fns are put into the same
	comdat group.

	* g++.dg/abi/mangle67.C: New test.

From-SVN: r230646