[C++ PATCH] Move mangling alias out of ::

[C++ PATCH] Move mangling alias out of ::

https://gcc.gnu.org/ml/gcc-patches/2017-10/msg00199.html
	gcc/cp/
	Move mangling aliases out of global namespace.
	* cp-tree.h (record_mangling): New.
	(maybe_remove_implicit_alias): Delete.
	* decl2.c (mangled_decls): New hash map.
	(generate_mangling_alias): Reimplement using mangled_decls.
	(record_mangling): New.
	* mangle.c (decl_implicit_alias_p,
	maybe_remove_implicit_alias): Delete.
	(mangle_decl): Use record_mangling.
	* name-lookup.c (supplement_binding_1): Remove
	maybe_remove_implicit_alias check.

	* call.c (convert_arg_to_ellipsis): Correct comment about passing
	by reference.

	gcc/testsuite/
	* g++.dg/abi/mangle41.C: Adjust diagnostics.

	libcc1/
	* libcp1plugin.cc (supplement_binding): Don't use
	maybe_remove_implicit_alias.

From-SVN: r253421