If you have the developer tools installed, CVS-tip builds directly on OSX and produces a carbon binary with no problems.

setenv CVSROOT :ext:anoncvs@savannah.gnu.org:/cvsroot/emacs
cvs checkout emacs
cd emacs
# I put my installation in /opt/emacs, and the X build seems to mess u
+p:
./configure --prefix=/opt/emacs --without-x
make bootstrap install
# one time only:
ln -s `pwd`/mac/Emacs.app ~/Desktop/
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