cannot use non-empty(comparable) struct as key of a map

[ltzmaxwell]

see

package main

type S struct {
	x int
}

func main() {
	m := make(map[S]string)
	m[S{x: 0}] = "test"
	println(m)
}

this compiles in Go but not in Gno, with error msg:
// Error:
// FieldType is a pseudotype with no elements

[omarsy]

I'm looking into it. Maybe I have a PR for that