[Bug middle-end/105469] "execution reached an unreachable program point" with -flto

["marxin at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105469

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
Reduced test-case:

namespace std {
template <class> struct char_traits;
template <typename _CharT, typename = char_traits<_CharT>> class basic_ostream;
struct ios_base {
  struct Init {
    Init();
  };
};
template <typename, typename> struct basic_ostream {
  void operator<<(const void *);
};
extern basic_ostream<char> cerr;
ios_base::Init __ioinit;
} // namespace std
enum Commit_Level { no_commit };
struct Writable {
  virtual void drop_fieldtimestampvalid_data() {}
  virtual void checkpoint(Commit_Level) {}
};
struct Posix_File {
  Posix_File();
  ~Posix_File();
};
Posix_File::Posix_File() {}
Posix_File::~Posix_File() {}
struct Readonly_Journal {
  Readonly_Journal();
  void play_until_checkpoint(Writable &writable) {
    writable.checkpoint(no_commit);
    std::cerr << "";
  }
};
Readonly_Journal::Readonly_Journal() {}
struct Writable_Journal : Readonly_Journal {
  Writable_Journal();
  ~Writable_Journal();
};
Writable_Journal::Writable_Journal() {}
Writable_Journal::~Writable_Journal() {}
struct Connection {
  virtual void push(Readonly_Journal &, long, bool) = 0;
};
template <typename Client_Data> struct Trans_NS_joedb_Client {
  Connection &connection;
  Client_Data data;
  Trans_NS_joedb_Client(Connection &, Posix_File file)
      : connection(connection), data(connection, file) {
    std::cerr << &data;
    data.update();
  }
};
struct Local_Connection : Connection {
  Posix_File file;
  void push(Readonly_Journal &, long, bool) {}
};
struct Generic_File_Database : Writable {
  Writable_Journal journal;
  Generic_File_Database();
  void checkpoint(Commit_Level) {}
};
struct Client_Data : Generic_File_Database {
  Client_Data(Connection &, Posix_File) {}
  void update() { journal.play_until_checkpoint(*this); }
};
struct Client : Trans_NS_joedb_Client<Client_Data> {
  Posix_File Client_local_file;
  Client() : Trans_NS_joedb_Client(connection, Client_local_file) {}
};
Generic_File_Database::Generic_File_Database() {}
struct Buggy_Client : Local_Connection, Client {};

int main() { Buggy_Client(); }