LspStart failed on Windows

[bstaint]

Description

LspStart failed on Windows.

Neovim version

NVIM v0.8.0-dev-708-g57ce6c2b8 Build type: RelWithDebInfo LuaJIT 2.1.0-beta3

Nvim-lspconfig version

ba25b747a3cff70c1532c2f28fcc912cf7b938ea

Operating system and version

Windows 10

Affected language servers

rust-analyzer

Steps to reproduce

--- a/lua/lspconfig/configs.lua
+++ b/lua/lspconfig/configs.lua
@@ -101,6 +101,7 @@ function configs.__newindex(t, config_name, config_def)
           local bufname = api.nvim_buf_get_name(bufnr)
           if util.bufname_valid(bufname) then
             local buf_dir = util.path.sanitize(bufname)
+            print(buf_dir, root_dir)
             if buf_dir:sub(1, root_dir:len()) == root_dir then
               M.manager.try_add_wrapper(bufnr)
             end

:LspStop
:LspStart

Actual behavior

output:

E:/Downloads/testrs/src/main.rs E:\Downloads\testrs

Expected behavior

No response

Minimal config

...

LSP log

...