The C compiler in the Go tree that's used to compile the C bits of the runtime already supports ARMv4 (unsurprisingly, since it was written a long time ago for Plan 9 and Inferno), only the Go compiler would need modifications.
The compiler suite is a pleasure to work on, really clear code, just like all the other code Ken Thompson wrote. Good luck.
I'll submit results if I get anywhere - might take a month or two :-)
Currently trying to a (any) toolchain online first to test the board and get a ucLinux kernel up (gcc cross-compiler + OpenOCD + Olimex ARM-JTAG + ThinkPad Ultrabay parallel port stack should be 'fun').
The compiler suite is a pleasure to work on, really clear code, just like all the other code Ken Thompson wrote. Good luck.