bug#64697: 29.0.92: cannot paste NUL on macOS (regression from Emacs 28)

[Eli Zaretskii]

> Cc: 64697@debbugs.gnu.org
> Date: Tue, 18 Jul 2023 10:22:21 +0100
> From: Alan Third <alan@idiocy.org>
> 
> > This was probably caused by 7e3c2b553f, where construction of a Lisp string 
> > was changed from make_string to build_string.
> 
> I considered this approach but wasn't aware of any situation where
> make_string would be better. You've found one. :)

I would actually recommend the opposite rule of thumb: only use
build_string if you have good reasons to do so.

Basically, build_string is unreliable with anything but fixed-value
pure-ASCII strings.