Greg Jandl to SDL I did some digging, and I think I've found a better solution. By including some additional .m4 macros in the acinclude directory (http://www.gnu.org/software/autoconf-archive/ax_check_compiler_flags.html, http://www.gnu.org/software/autoconf-archive/ax_gcc_archflag.html and http://www.gnu.org/software/autoconf-archive/ax_gcc_x86_cpuid.html) then using the patch below (same as previous patch + one line change to configure.in), SDL will build correctly out of the box. The arch can then be overridden by --with-gcc-arch=<arch> (most will probably want to build with i686 there for general distribution) or --without-gcc-arch, to disable setting the arch all together. On my Atom netbook, I get -march=PentiumPro by default, which works great, as does --with-gcc-arch=i686.

#!/bin/csh

###
## This script creates "Xcode.tar.gz" in the parent directory
###

# remove build products
rm -rf SDL/build
rm -rf SDLTest/build

# remove Finder info files
find . -name ".DS_Store" -exec rm "{}" ";"

# remove user project prefs
find . -name "*.pbxuser*" -exec rm "{}" ";"
find . -name "*.mode*" -exec rm "{}" ";"
find . -name "*.perspective*" -exec rm "{}" ";"

# create the archive
(cd .. && gnutar -zcvf Xcode.tar.gz Xcode)