PR c++/49107
	* cp-tree.def (DEFERRED_NOEXCEPT): New.
	* cp-tree.h (struct tree_deferred_noexcept): New.
	(DEFERRED_NOEXCEPT_PATTERN, DEFERRED_NOEXCEPT_ARGS): New.
	(DEFERRED_NOEXCEPT_SPEC_P): New.
	(enum cp_tree_node_structure_enum): Add TS_CP_DEFERRED_NOEXCEPT.
	(union lang_tree_node): Add tree_deferred_noexcept.
	(maybe_instantiate_noexcept): Declare.
	* cp-objcp-common.c (cp_tree_size): Handle DEFERRED_NOEXCEPT.
	* error.c (dump_exception_spec): Likewise.
	* cxx-pretty-print.c (pp_cxx_exception_specification): Likewise.
	* ptree.c (cxx_print_xnode): Likewise.
	* tree.c (cp_tree_equal): Likewise.
	* decl.c (cp_tree_node_structure): Likewise.
	(duplicate_decls): Call maybe_instantiate_noexcept.
	* except.c (build_noexcept_spec): Handle DEFERRED_NOEXCEPT.
	(nothrow_spec_p, type_noexcept_p, type_throw_all_p): Check
	DEFERRED_NOEXCEPT_SPEC_P.
	* typeck2.c (merge_exception_specifiers): Likewise.
	* decl2.c (mark_used): Call maybe_instantiate_noexcept.
	* method.c (process_subob_fn, defaulted_late_check): Likewise.
	* pt.c (tsubst_exception_specification): Add defer_ok parm.
	Build DEFERRED_NOEXCEPT.
	(maybe_instantiate_noexcept): New.
	(tsubst, regenerate_decl_from_template, instantiate_decl): Adjust.
	* search.c (check_final_overrider): Call maybe_instantiate_noexcept.

From-SVN: r174820