Indeed. I just tried with just "make" and I got what Ital described,
so it is not connected to the environment variable issue that I
mentioned...
I believe #27645 proposes to remove this quirk.
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=27645
It's a fix for a related issue; the point of the patch in that bug
report is to be able to run GUI Emacs from src/emacs, not from an
incomplete application bundle in nextstep/Emacs.app. Thankfully,
Emacs already has code (I think) to set 'load-path' and the like
specially when we run from 'src/emacs', so the only modification I
needed to make to the NS-specific code was to let the OS allow the
Emacs frame to have focus. This change should prevent people
developing on NS from having to run 'make install' all the time to get
a working GUI build, since 'src/emacs -q' will work.