[swhipple]

The mkstemp you are seeing is probably the one from gnulib. A lot of GNU software uses their own versions if they detect the platform one is broken; it may be incorrectly replacing it in this case.

https://www.gnu.org/software/gnulib/manual/html_node/mkstemp...

https://github.com/emacs-mirror/emacs/blob/65eee8392ff95f58f...