panics for nil pointer dereferences cannot be recovered

[thehowl]

Gno currently doesn't allow using recover() when a nil pointer has been referenced. This came up with adapting fmt (#3847), where I cannot show <nil> for a case like the following:

func main() {
	v := (*time.Time)(nil)
	fmt.Println(v)
}

v.String() panics because String() expects a non-pointer receiver. The fmt code should be able to recover() from this panic, and show a "<nil>" instead, however this is not the case.

[thehowl]

Sorry, this actually works, my mistake!