[Bug c++/84126] [8 Regression] ICE in variadic generic lambda inside a template function calling a function with arguments by reference

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84126

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Started with r257018:

commit 2100de5308865b06be2b235ed159b5af9a9a67a5
Author: jason <jason@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Wed Jan 24 15:20:53 2018 +0000

            PR c++/82249 - wrong mismatched pack length error.

            * pt.c (extract_fnparm_pack, tsubst_pack_expansion): Handle
            unsubstituted function parameter pack.