proposal: runtime: mapaccess shouldn’t panic on nil map

[gbbr]

I have a feeling this might have been discussed before, but I couldn’t find an issue. If it exists, please close this one.

Is there any benefit in having mapaccess panic on nil maps?
https://github.com/golang/go/blob/master/src/runtime/map.go#L57

Is there any down side to having a map automatically “made” (makemap) when it is nil? This would mirror the behaviour of slices too: appending to a nil slice creates it.

[bcmills]

See #28133 (comment).

[gbbr]

Thanks! 🙇‍♂️