[PATCH] fchmodat/fstatat: fix regression with empty `pathname`

[Jeremy Drake]

On Tue, 27 Jun 2023, Johannes Schindelin wrote:

> In 4b8222983f (Cygwin: fix errno values set by readlinkat, 2023-04-18)
> the code of `readlinkat()` was adjusted to align the `errno` with Linux'
> behavior.
>
> 	I noticed this issue when one of my workflows failed consistently
> 	while trying to untar an archive containing a symbolic link and
> 	claiming this:
>
> 		Cannot change mode to rwxr-xr-x: Not a directory
>

I wonder if this is related to the issue from the thread
https://cygwin.com/pipermail/cygwin/2023-May/253738.html (sounds like it).
If so, tar was
rebuilt to pick up the new behavior in 3.4.7 (presumably via configure
checks), it may need another rebuild to pick up the fixed behavior after
this fix.