Vague popularity icons sounds good to me.
As for a list, can someone who wants it please explain how we can fairly distinguish hobby compilers from others?
Does Tcc count, or is the guy who wrote Qemu too big and clever? Tell me how you'd exclude Gcc, on which, I'm almost 100% certain, some people are working on as part of their hobby right now. (If they're not taking a break after watching the launch to Mars.) Or KenCC? Ken Thompson was paid, but seems to have had a whole lot of freedom for large sections of his working life - a "paid hobby" perhaps? Should we exclude something he probably wanted to work on just because he was paid? KenCC shows a whole lot of personal advancement too, hardly seeming like it could come from the guy who bikeshedded BCPL in 1970 to make it look simpler, and who claimed he couldn't cope with anything complex. (He gives me hope!
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