[libcxx] Avoid infinite recursion in create_directories, if the root directory doesn't exist

Differential Revision: https://reviews.llvm.org/D97618

GitOrigin-RevId: 99c7b532946508efcf6cd978d86ee24b2a66d096
diff --git a/src/filesystem/operations.cpp b/src/filesystem/operations.cpp
index f112168..35f6937 100644
--- a/src/filesystem/operations.cpp
+++ b/src/filesystem/operations.cpp
@@ -1019,6 +1019,8 @@
     if (not status_known(parent_st))
       return err.report(m_ec);
     if (not exists(parent_st)) {
+      if (parent == p)
+        return err.report(errc::invalid_argument);
       __create_directories(parent, ec);
       if (ec && *ec) {
         return false;