[Bug c++/96676] New: Segmentation fault on parsing simple variadic template function call

["ivan.leonov.d at yandex dot ru" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96676

            Bug ID: 96676
           Summary: Segmentation fault on parsing simple variadic template
                    function call
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ivan.leonov.d at yandex dot ru
  Target Milestone: ---

Sample code:

template < typename T, typename... TYPES >
struct A {
    template < TYPES... types >
    void Get() { }
};

void f() {}

int main() {
    A<int, decltype(&f)> a;
    a.Get<&f>();
}


Error and Backtrace:

prog.cc: In function 'int main()':
prog.cc:13:15: internal compiler error: Segmentation fault
   13 |     a.Get<&f>();
      |               ^
0xc026af crash_signal
        ../../source/gcc/toplev.c:327
0x73a995 tsubst_pack_expansion(tree_node*, tree_node*, int, tree_node*)
        ../../source/gcc/cp/pt.c:12871
0x7356d1 coerce_template_parameter_pack
        ../../source/gcc/cp/pt.c:8538
0x7356d1 coerce_template_parms
        ../../source/gcc/cp/pt.c:8830
0x747bc8 fn_type_unification(tree_node*, tree_node*, tree_node*, tree_node*
const*, unsigned int, tree_node*, unification_kind_t, int, conversion**, bool,
bool)
        ../../source/gcc/cp/pt.c:21078
0x619282 add_template_candidate_real
        ../../source/gcc/cp/call.c:3417
0x6199bc add_template_candidate
        ../../source/gcc/cp/call.c:3502
0x6199bc add_candidates
        ../../source/gcc/cp/call.c:5883
0x61a9cc add_candidates
        ../../source/gcc/cp/call.c:5798
0x61a9cc build_new_method_call_1
        ../../source/gcc/cp/call.c:10271
0x61b6ff build_new_method_call(tree_node*, tree_node*, vec<tree_node*, va_gc,
vl_embed>**, tree_node*, int, tree_node**, int)
        ../../source/gcc/cp/call.c:10478
0x6fcdd7 cp_parser_postfix_expression
        ../../source/gcc/cp/parser.c:7513
0x6dfa9a cp_parser_binary_expression
        ../../source/gcc/cp/parser.c:9641
0x6e13de cp_parser_assignment_expression
        ../../source/gcc/cp/parser.c:9946
0x6e16e2 cp_parser_expression
        ../../source/gcc/cp/parser.c:10114
0x6e41b8 cp_parser_expression_statement
        ../../source/gcc/cp/parser.c:11774
0x6eef10 cp_parser_statement
        ../../source/gcc/cp/parser.c:11570
0x6f076d cp_parser_statement_seq_opt
        ../../source/gcc/cp/parser.c:11921
0x6f0820 cp_parser_compound_statement
        ../../source/gcc/cp/parser.c:11871
0x7078da cp_parser_function_body
        ../../source/gcc/cp/parser.c:23170