[Bug libstdc++/87227] New: doesn't work std::filesystem::directory_options::follow_directory_symlink

[faithandbrave at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87227

            Bug ID: 87227
           Summary: doesn't work
                    std::filesystem::directory_options::follow_directory_s
                    ymlink
           Product: gcc
           Version: 8.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: faithandbrave at gmail dot com
  Target Milestone: ---

#include <iostream>
#include <filesystem>
#include <fstream>

namespace fs = std::filesystem;

int main()
{
  fs::create_directory("dir_a");
  std::ofstream{"dir_a/a.txt"};

  fs::create_directory("dir_b");
  std::ofstream{"dir_b/b.txt"};
  fs::create_directory_symlink("dir_a", "dir_b/dir_a");

  for (const fs::directory_entry& x : fs::recursive_directory_iterator(
                                        "dir_b",
                                       
fs::directory_options::follow_directory_symlink)) {
    std::cout << x.path() << std::endl;
  }
}

expected result:
"dir_b/b.txt"
"dir_b/dir_a"
"dir_b/dir_a/a.txt"

actual result:
"dir_b/b.txt"
"dir_b/dir_a"