Some bright spark has modded the 1.4.2 Go runtime to compile to mips32 / mips32le targets. I've just tested on another MIPS platform and hello world works, though I don't know more than that yet. I'm setting up a Black Swift so I can test, but meanwhile here's the link:
Compilation: Remember to prefix the 'make.bash' script with environment variables 'GOROOT' (for the intended install destination, I recommend /opt/mipsgo), 'GOOS=linux' and 'GOARCH=mips32'. Then, when built, copy the whole tree to /opt/mipsgo and then use it by prefixing PATH and setting GOOS/GOARCH to linux/mips32. I use it like this, which is easy to alias in bashrc:
$ PATH=/opt/mipsgo:$PATH GOOS=linux GOARCH=mips32 go build helloworld.go
Like I said, untested on Black Swift yet but works on my MIPS OpenWRT router.
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