Glenn Morris <rgm@gnu.org> schrieb am Fr., 21. Sep. 2018 um 17:36 Uhr:

Philipp Stephani wrote:

> + $(MKDIR_P) -m 0755 $(includedir)

I don't remember how portable that is, but everywhere else in Emacs's
Makefiles uses: umask 022 && ${MKDIR_P} "...".

Good idea, done.

And should this file only be installed in a --with-modules build?

I considered that, but I think it's simpler to install it unconditionally. Users can use emacs-module.h to build modules even if their version of Emacs doesn't support them.