[Bug c++/79550] New: ICE in tsubst, at cp/pt.c:13474 with partial specialization of auto... template parameter pack

[rs2740 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79550

            Bug ID: 79550
           Summary: ICE in tsubst, at cp/pt.c:13474 with partial
                    specialization of auto... template parameter pack
           Product: gcc
           Version: 7.0.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rs2740 at gmail dot com
  Target Milestone: ---

template <auto...>
struct meow;

template <auto C>
struct meow<C> { };

template struct meow<1>;

prog.cc: In substitution of 'template<auto C> struct meow<C> [with auto C =
1]':
prog.cc:7:17:   required from here
prog.cc:7:17: internal compiler error: in tsubst, at cp/pt.c:13474
 template struct meow<1>;
                 ^~~~~~~
0x5d6a8c tsubst(tree_node*, tree_node*, int, tree_node*)
        ../../source/gcc/cp/pt.c:13474
0x5df37c tsubst_template_args
        ../../source/gcc/cp/pt.c:11638
0x5d5d5b tsubst(tree_node*, tree_node*, int, tree_node*)
        ../../source/gcc/cp/pt.c:13695
0x5d49f7 get_partial_spec_bindings
        ../../source/gcc/cp/pt.c:21511
0x5d4cbd most_specialized_partial_spec
        ../../source/gcc/cp/pt.c:21741
0x5ef83b instantiate_class_template_1
        ../../source/gcc/cp/pt.c:10183
0x5ef83b instantiate_class_template(tree_node*)
        ../../source/gcc/cp/pt.c:10751
0x652235 complete_type(tree_node*)
        ../../source/gcc/cp/typeck.c:133
0x5ead7b do_type_instantiation(tree_node*, tree_node*, int)
        ../../source/gcc/cp/pt.c:22011
0x64661f cp_parser_explicit_instantiation
        ../../source/gcc/cp/parser.c:16210
0x627581 cp_parser_declaration
        ../../source/gcc/cp/parser.c:12467
0x64d05b cp_parser_declaration_seq_opt
        ../../source/gcc/cp/parser.c:12391
0x64d342 cp_parser_translation_unit
        ../../source/gcc/cp/parser.c:4366
0x64d342 c_parse_file()
        ../../source/gcc/cp/parser.c:38425
0x71b2a3 c_common_parse_file()
        ../../source/gcc/c-family/c-opts.c:1107
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