There is an thread from a couple of months ago (viewtopic.php?f=9&t=11177) questioning this, to which the response was to read this:
https://github.com/archlinuxarm/PKGBUILDs
I had the same question, but the above confuses me. Sorry if I'm missing something, but are these really the PKGBUILDs used for ARM builds? You obviously can't just download and run "makepkg" against them:
$this->bbcode_second_pass_code('', '==> ERROR: retroarch is not available for the 'armv6h' architecture.')
If the "buildarch" variable is the key here, the README doesn't appear to say where this is set. Any help would be appreciated!