[Bug c++/126323] New: ICE when parsing #pragma GCC novector inside a class definition before a for statement

[s.kimura.h41104 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126323

            Bug ID: 126323
           Summary: ICE when parsing #pragma GCC novector inside a class
                    definition before a for statement
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: s.kimura.h41104 at gmail dot com
  Target Milestone: ---

Compiler Explorer: https://godbolt.org/z/zG55d1Kjo

Reproducer:
```
class C {
  #pragma GCC novector
  for (int i = 0; i < 2; i++)
    ;
};
```

Backtrace:
<source>:3:12: internal compiler error: tree check: expected tree that contains
'decl with visibility' structure, have 'parm_decl' in start_decl, at
cp/decl.cc:6658
    3 |   for (int i = 0; i < 2; i++)
      |            ^
0x2b4dc08 diagnostics::context::diagnostic_impl(rich_location*,
diagnostics::metadata const*, diagnostics::option_id, char const*,
__va_list_tag (*) [1], diagnostics::kind)
        ???:0
0x2b4284b internal_error(char const*, ...)
        ???:0
0xa391e9 tree_contains_struct_check_failed(tree_node const*,
tree_node_structure_enum, char const*, int, char const*)
        ???:0
0xd90413 c_parse_file()
        ???:0
0xf22c69 c_common_parse_file()
        ???:0

This ICE goes back to gcc-14:
https://godbolt.org/z/x1d57xosP