[Bug c++/96048] New: ICE in get_local_decls, at cp/name-lookup.c:3591

[haoxintu at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96048

            Bug ID: 96048
           Summary: ICE in get_local_decls, at cp/name-lookup.c:3591
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: haoxintu at gmail dot com
  Target Milestone: ---

This invalid code, bug.cc, makes GCC-trunk ICE.

$cat bug.cc
struct a {template <class> class A;};
a : b ( auto ) ( class { });


$g++ -c -w bug.cc
bug.cc:2:3: error: found ‘:’ in nested-name-specifier, expected ‘::’
    2 | a : b ( auto ) ( class { });
      |   ^
      |   ::
bug.cc:2:18: error: template definition of non-template ‘struct a::<unnamed>’
    2 | a : b ( auto ) ( class { });
      |                  ^~~~~
bug.cc:2:27: internal compiler error: in get_local_decls, at
cp/name-lookup.c:3591
    2 | a : b ( auto ) ( class { });
      |                           ^
0x63d349 get_local_decls()
        ../../gcc/cp/name-lookup.c:3591
0x97a185 pop_bindings_and_leave_scope()
        ../../gcc/cp/name-lookup.c:2065
0x9b0969 cp_parser_direct_declarator
        ../../gcc/cp/parser.c:21336
0x9b0969 cp_parser_declarator
        ../../gcc/cp/parser.c:21109
0x9c4ca6 cp_parser_init_declarator
        ../../gcc/cp/parser.c:20609
0x9a67a2 cp_parser_simple_declaration
        ../../gcc/cp/parser.c:13785
0x9cfa16 cp_parser_declaration
        ../../gcc/cp/parser.c:13484
0x9d015a cp_parser_translation_unit
        ../../gcc/cp/parser.c:4761
0x9d015a c_parse_file()
        ../../gcc/cp/parser.c:44043
0xae920b c_common_parse_file()
        ../../gcc/c-family/c-opts.c:1190
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

$g++ --version
++ (GCC) 11.0.0 20200630 (experimental)
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