[Bug c++/84839] [6/7/8 Regression] ICE (Segmentation fault) when `decltype` is used with parameter pack

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84839

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Tue Mar 13 18:57:10 2018
New Revision: 258500

URL: https://gcc.gnu.org/viewcvs?rev=258500&root=gcc&view=rev
Log:
        PR c++/84839 - ICE with decltype of parameter pack.

        * pt.c (tsubst_pack_expansion): Set cp_unevaluated_operand while
        instantiating dummy parms.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/variadic-nested2.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/pt.c