T := pkg.Scope().Lookup("T").Type()
	name := "m"
	for _, recv := range []Type{T, NewPointer(T)} {
		// LookupFieldOrMethod and NewMethodSet must match:
		// either both find m or neither finds it.
		obj1, _, _ := LookupFieldOrMethod(recv, false, pkg, name)
		mset := NewMethodSet(recv)
		if (obj1 != nil) != (mset.Len() == 1) {
			t.Fatalf("lookup(%v.%s): got obj = %v, mset = %v", recv, name, obj1, mset)
		}

		t.Fatal(err)
	}
	res, err := downstream.Recv()
	if err != nil {
		t.Fatal(err)
	}

	if res == nil || res.TypeUrl != v3.ClusterType {
		t.Fatalf("Expected to get cluster response but got %v", res)
	}
	err = downstream.Send(&discovery.DeltaDiscoveryRequest{TypeUrl: v3.ListenerType, Node: node})
	if err != nil {
		t.Fatal(err)
	}
	res, err = downstream.Recv()
	if err != nil {
		t.Fatal(err)
	}

	s = strings.TrimPrefix(s, "*")
	pkg, name, ok = splitDocName(s)
	var recv string
	if ok {
		pkg, recv, _ = splitDocName(pkg)
	}
	if pkg != "" {
		if err := module.CheckImportPath(pkg); err != nil {
			return "", "", false
		}
	}
	if recv != "" {
		name = recv + "." + name
	}
	return pkg, name, true
}

! stderr 'Alias'

-- go.mod --
module example.com
go 1.12

-- a.go --
package a

/*
typedef int T;
*/
import "C"

func (C.T) f() {}
func (recv *C.T) g() {}

// The check is more education than enforcement,
// and is easily defeated using a type alias.
type Alias = C.T
func (Alias) h() {}

			ch := n.Chan
			cond = mkcall1(chanfn("selectnbsend", 2, ch.Type()), types.Types[types.TBOOL], r.PtrInit(), ch, n.Value)

		case ir.OSELRECV2:
			n := n.(*ir.AssignListStmt)
			recv := n.Rhs[0].(*ir.UnaryExpr)
			ch := recv.X
			elem := n.Lhs[0]
			if ir.IsBlank(elem) {
				elem = typecheck.NodNil()
			}
			cond = typecheck.TempAt(base.Pos, ir.CurFunc, types.Types[types.TBOOL])

		return &emptyInterface
	}

	// set method receivers if necessary
	typ := (*Checker)(nil).newInterface()
	for _, m := range methods {
		if sig := m.typ.(*Signature); sig.recv == nil {
			sig.recv = NewVar(m.pos, m.pkg, "", typ)
		}
	}

	// sort for API stability
	sortMethods(methods)

	typ.methods = methods
	typ.embeddeds = embeddeds
	typ.complete = true

	return typ
}

package main

import "runtime"

const N = 1000 // sent messages
const M = 10   // receiving goroutines
const W = 2    // channel buffering
var h [N]int   // marking of send/recv

func r(c chan int, m int) {
	for {
		select {
		case r := <-c:
			if h[r] != 1 {
				println("r",
					"m=", m,
					"r=", r,
					"h=", h[r])
				panic("fail")
			}
			h[r] = 2
		}
	}

		if !ok {
			return // e.g. var or builtin
		}
		if sig := fn.Type().(*types.Signature); sig.Recv() != nil {
			// method (e.g. foo.String())
			if types.Identical(sig, sigNoArgsStringResult) {
				if stringMethods[fn.Name()] {
					pass.Reportf(call.Lparen, "result of (%s).%s call not used",
						sig.Recv().Type(), fn.Name())
				}
			}
		} else {
			// package-level function (e.g. fmt.Errorf)

			i := v.MapRange()
			for i.Next() {
				if !yield(i.Key()) {
					return
				}
			}
		}
	case Chan:
		return func(yield func(Value) bool) {
			for value, ok := v.Recv(); ok; value, ok = v.Recv() {
				if !yield(value) {
					return
				}
			}
		}
	}
	panic("reflect: " + v.Type().String() + " cannot produce iter.Seq[Value]")
}

		for _, size := range sizes {
			t.Run(strconv.Itoa(size), func(t *testing.T) {
				testSendFile(t, "tcp", int64(size))
			})
		}
	})
}

func testSendFile(t *testing.T, proto string, size int64) {
	dst, src, recv, data, hook := newSendFileTest(t, proto, size)

	// Now call WriteTo (through io.Copy), which will hopefully call poll.SendFile
	n, err := io.Copy(dst, src)
	if err != nil {
		t.Fatalf("io.Copy error: %v", err)
	}