-- go.mod --
module m

go 1.20
-- main.go --
package main

import "m/sub"

func main() { sub.F() }
-- sub/sub.go --
package sub

type iface interface{ m() }

func F() {
	f := func(rt []iface) []iface {
		return append([]iface{}, rt...)
	}
	f(nil)

	_ = i + false     // ERROR "invalid operation.*mismatched types.*int and untyped bool"
	_ = iface + 1     // ERROR "invalid operation.*mismatched types.*interface *{} and int"
	_ = iface + 1.0   // ERROR "invalid operation.*mismatched types.*interface *{} and float64"
	_ = iface + false // ERROR "invalid operation.*mismatched types.*interface *{} and bool"

func (t *TypeParam) Underlying() Type {
	return t.iface()
}

func (t *TypeParam) String() string { return TypeString(t, nil) }

// ----------------------------------------------------------------------------
// Implementation

func (t *TypeParam) cleanup() {
	t.iface()
	t.check = nil
}

// iface returns the constraint interface of t.
func (t *TypeParam) iface() *Interface {
	bound := t.bound

// license that can be found in the LICENSE file.

// Ensure that late expansion correctly set OpLoad argument type interface{}

package p

type iface interface {
	m()
}

type it interface{}

type makeIface func() iface

func f() {
	var im makeIface
	e := im().(it)
	g(e)
}

//go:noinline

	var x X
	// BAD: &i should not escape
	x.p1 = &i
	var iface interface{} = x // ERROR "x does not escape"
	x1 := iface.(X)
	sink = x1.p2
}

func field17() {
	i := 0 // ERROR "moved to heap: i$"
	var x X
	x.p1 = &i
	var iface interface{} = x // ERROR "x does not escape"
	x1 := iface.(X)
	sink = x1.p1
}

func field18() {
	i := 0 // ERROR "moved to heap: i$"

				}

				var iface interface{}
				if err := modePair.dec.Unmarshal(cborFromOriginal, &iface); err != nil {
					t.Fatalf("unexpected error from Unmarshal into %T: %v", &iface, err)
				}

				cborFromIface, err := modePair.enc.Marshal(iface)
				if err != nil {
					t.Fatalf("unexpected error from Marshal of iface: %v", err)
				}

				{
					// interface{} to interface{}

                String iface = INTERFACES.get(lep.substring(6));
                if ( iface != null ) {
                    int c, p;
                    c = iface.indexOf(':');
                    p = iface.indexOf('.', c + 1);
                    this.uuid = new UUID(iface.substring(0, c));
                    this.major = Integer.parseInt(iface.substring(c + 1, p));

	t21 int = a /* ERRORx `cannot use .* variable declaration` */
)

// Various more complex expressions
var (
	u1 = x /* ERROR "not an interface" */ .(int)
	u2 = iface.([]int)
	u3 = iface.(a /* ERROR "not a type" */ )
	u4, ok = iface.(int)
	u5, ok2, ok3 = iface /* ERROR "assignment mismatch" */ .(int)
)

// Constant expression initializations
var (
	v1 = 1 /* ERROR "mismatched types untyped int and untyped string" */ + "foo"

	*myInt
}

var val = 1234

var valNotInHeap = notInHeap{i: val}

func main() {
	i := val
	check(i)
	mi := myInt{f: &valNotInHeap}
	check(mi.Get())
	ifv := iface(mi)
	check(ifv.Get())
	ifv = iface(&mi)
	check(ifv.Get())
	em := embed{&mi}
	check(em.Get())
	ifv = em
	check(ifv.Get())
	ifv = &em
	check(ifv.Get())
}

func check(v int) {
	if v != val {
		panic(v)
	}

		embeddeds, ecopied := subst.typeList(t.embeddeds)
		if mcopied || ecopied {
			iface := subst.check.newInterface()
			iface.embeddeds = embeddeds
			iface.embedPos = t.embedPos
			iface.implicit = t.implicit
			assert(t.complete) // otherwise we are copying incomplete data
			iface.complete = t.complete
			// If we've changed the interface type, we may need to replace its