What version of Go are you using (go version)?

go1.10rc1 linux/amd64

Does this issue reproduce with the latest release?

Yes, and with tip. (851e98f)

What operating system and processor architecture are you using (go env)?

Ubuntu 16.04.

What did you do?

Attempting to use go/types to do fast type checking of a large repository reveals a problem:

func a() {
        var x int
        func() {
        	x = 3
        }()
}

Is reported as x declared but not used by go/types, but does not produce an error in the compiler.

Demo: https://play.golang.org/p/oi6haYy6cXt

What did you expect to see?

I expected go/types to return identical type errors as actually compiling.

What did you see instead?

Different errors.