Here are some notes from this Google Groups thread. In it, the author writes:
While I made some progress in trying to install Py3k from source (for the first time), it has failed... Here are the steps I went through (not necessarily in that order - except for those that matter). 1. After installing Leopard, install Xcode tools from the dvd - even if you had done so with a previous version (they need to be updated - trust me :-) 2. Download Python 3.0a1 3. Unpack the archive. 4. Go to /usr/local and make a directory "sudo mkdir py3k" (This is probably not needed, but that's what I did). 5. From the directory where the Python 3.0a1 was unpacked run ./configure --prefix=/usr/local/py3k 6. run "make" This last step failed with the following error message: gcc -fno-strict-aliasing -Wno-long-double -no-cpp-precomp -mno-fused- madd -DNDEBUG -g -O3 -Wall -Wstrict-prototypes -I. -I./Include - DPy_BUILD_CORE -c ./Modules/posixmodule.c -o Modules/posixmodule.o ./Modules/posixmodule.c: In function 'posix_setpgrp': ./Modules/posixmodule.c:3769: error: too few arguments to function 'setpgrp' make: *** [Modules/posixmodule.o] Error 1
Further down the thread he posts a fix:
Following Martin v Löwis's suggestion, I looked at
http://bugs.python.org/issue1358
and added the line
#define SETPGRP_HAVE_ARG
by hand to pyconfig.h (after it was created by configure). Then
6. run "make"
7. run "make test" (one test failed; this step likely unnecessary)
8. sudo make altinstall
9. sudo ln /usr/local/bin/py3k/python3.0 /usr/bin/python3.0
10. type "python"
11. print("Hello world!")
12. Be happy!