[Bug c++/80396] New builtin to make std::make_integer_sequence efficient and scalable

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80396

--- Comment #1 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Tue May 23 20:14:01 2017
New Revision: 248384

URL: https://gcc.gnu.org/viewcvs?rev=248384&root=gcc&view=rev
Log:
        PR c++/80396 - built-in for make_integer_sequence.

        * pt.c (builtin_pack_fn_p, builtin_pack_call_p)
        (expand_integer_pack, expand_builtin_pack_call): New.
        (find_parameter_packs_r): Check builtin_pack_call_p.
        (check_for_bare_parameter_packs): Handle it.
        (tsubst_pack_expansion): Call expand_builtin_pack_call.
        (declare_integer_pack): New.
        (init_template_processing): Call it.
        * decl2.c (mark_used): Check builtin_pack_fn_p.

Added:
    trunk/gcc/testsuite/g++.dg/ext/integer-pack1.C
    trunk/gcc/testsuite/g++.dg/ext/integer-pack2.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/cp-tree.h
    trunk/gcc/cp/decl2.c
    trunk/gcc/cp/parser.c
    trunk/gcc/cp/pt.c
    trunk/gcc/doc/extend.texi