Beginner installing org-mode 9.1.2 from git fails on homebrew emacs-mac

[Umbromancer <umbromancer@gmail.com>]

Hi all,

This is my first post on the list, and an definitively an emacs/org-mode newbe.

I've just upgraded to emacs 25.3.1 via homebrew (emacs-mac) and the
included org-version is 8.2.10. I'm trying to setup the git stable
release_9.1.2 as per suggestion on the worg faq. I've cloned the git
repo and duplicated default.mk into local.mk and edited it so as to
point to the homebrew Emacs location.

I've upgraded org-mode on my previous Emacs 24 install using the
"same" method. The only difference being previously I used the
org-mode stable download from org-mode.org instead of the git sources.

After editing local.mk and issuing the make commands, I get:
$ make cleanall
...
$ make install
Miguels-MBP:org-mode me$ make install
/Library/Developer/CommandLineTools/usr/bin/make -C doc install
org-version: 9.1.2 (release_9.1.2)
makeinfo --no-split org.texi -o org
/Users/me/elisp/org-mode/doc//docstyle.texi:3: warning: unrecognized
encoding name `UTF-8'.
if [ ! -d /usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/info/emacs
]; then install -m 755 -d
/usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/info/emacs; else
true; fi ;
install -m 644 -p org
/usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/info/emacs
install-info --infodir=/usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/info/emacs
org
/Library/Developer/CommandLineTools/usr/bin/make -C etc install
for dir in styles schema ; do \
      if [ ! -d
/usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/emacs/25.3/etc/org/${dir}
] ; then \
        install -m 755 -d
/usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/emacs/25.3/etc/org/${dir}
; \
      fi ; \
      install -m 644 -p ${dir}/*
/usr/local/Cellar/emacs-mac/emacs-25.3-mac-6.8/share/emacs/25.3/etc/org/${dir}
; \
    done ;
/Library/Developer/CommandLineTools/usr/bin/make -C lisp install
rm -f org-version.el org-loaddefs.el org-version.elc org-loaddefs.elc
org-install.elc
org-version: 9.1.2 (release_9.1.2)
Loading /Users/me/elisp/org-mode/lisp/org-compat.el (source)...
Cannot open load file: cl-lib
make[1]: *** [org-version.el] Error 255
make: *** [install-lisp] Error 2
Miguels-MBP:org-mode me$

cl-lib is of course available when I run Emacs.
I'm mostly likely missing something which fails to be obvious for me...

Thanks in advance for all the help,
Miguel