sys/mount.h vs fcntl.h

[Florian Weimer]

* DJ Delorie:

> commit a36999aed5cd36d54a828ab4b41426aef7d870f2
> Author: DJ Delorie <dj@redhat.com>
> Date:   Mon Jan 26 22:24:42 2026 -0500
>
>     include: isolate __O_CLOEXEC flag for sys/mount.h and fcntl.h
>     
>     Including sys/mount.h should not implicitly include fcntl.h
>     as that causes namespace pollution and conflicts with kernel
>     headers.  It only needs O_CLOEXEC for OPEN_TREE_CLOEXEC
>     (although it shouldn't need that, but it's defined that way)
>     so we provide that define (a private version) separately.

To make bits/cloexec.h an installed hedader, you need to update
sysdeps_headers in sysdeps/unix/sysv/linux/Makefile.

Thanks,
Florian