Using clang instead of gcc, since that works with Lion (cannot get gcc to work)
Updated Makefile command dependencies
Added some debug outputs when trying to locate gdb, DeveloperDiskImage.dmg and DeviceSupport directory.
Now looking for above files in more places too. Make sure you have a symbolic link in the directory containing different versions DevelopDiskImage.dmg pointing to Latest (whatever your latest may be). This will increase chances of something being found.