func InitConst(n *ir.Name, noff int64, c ir.Node, wid int) {
	if n.Op() != ir.ONAME {
		base.Fatalf("InitConst n op %v", n.Op())
	}
	if n.Sym() == nil {
		base.Fatalf("InitConst nil n sym")
	}
	if c.Op() == ir.ONIL {
		return
	}
	if c.Op() != ir.OLITERAL {
		base.Fatalf("InitConst c op %v", c.Op())
	}
	s := n.Linksym()
	switch u := c.Val(); u.Kind() {
	case constant.Bool:

		return n
	}
	if !n.Type().IsUntyped() {
		// Already typed; nothing to do.
		return n
	}

	// Nil is technically not a constant, so handle it specially.
	if n.Type().Kind() == types.TNIL {
		if n.Op() != ir.ONIL {
			base.Fatalf("unexpected op: %v (%v)", n, n.Op())
		}
		n = ir.Copy(n)
		if t == nil {
			base.Fatalf("use of untyped nil")
		}

		if !t.HasNil() {
			// Leave for caller to handle.
			return n
		}

	OMAKESLICE:        8,
	OMAKESLICECOPY:    8,
	OMAKE:             8,
	OMAPLIT:           8,
	OMAX:              8,
	OMIN:              8,
	ONAME:             8,
	ONEW:              8,
	ONIL:              8,
	ONONAME:           8,
	OPANIC:            8,
	OPAREN:            8,
	OPRINTLN:          8,
	OPRINT:            8,
	ORUNESTR:          8,
	OSLICE2ARR:        8,
	OSLICE2ARRPTR:     8,

// and then returns tmp.
func (o *orderState) cheapExpr(n ir.Node) ir.Node {
	if n == nil {
		return nil
	}

	switch n.Op() {
	case ir.ONAME, ir.OLITERAL, ir.ONIL:
		return n
	case ir.OLEN, ir.OCAP:
		n := n.(*ir.UnaryExpr)
		l := o.cheapExpr(n.X)
		if l == n.X {
			return n
		}
		a := ir.Copy(n).(*ir.UnaryExpr)
		a.X = l
		return typecheck.Expr(a)
	}

			}
			c <- struct{}{}
		}()
		runtime.Goexit()
	}()
	// Note: if the defer fails to run, we will get a deadlock here
	<-c
}

func TestGoNil(t *testing.T) {
	output := runTestProg(t, "testprog", "GoNil")
	want := "go of nil func value"
	if !strings.Contains(output, want) {
		t.Fatalf("output:\n%s\n\nwant output containing: %s", output, want)
	}
}

func TestMainGoroutineID(t *testing.T) {

		}

		// Recognize a few common expressions that can be evaluated within
		// the wrapper, so we don't need to allocate space for them within
		// the closure.
		switch arg.Op() {
		case ir.OLITERAL, ir.ONIL, ir.OMETHEXPR, ir.ONEW:
			return
		case ir.ONAME:
			arg := arg.(*ir.Name)
			if arg.Class == ir.PFUNC {
				return // reference to global function
			}
		case ir.OADDR:
			arg := arg.(*ir.AddrExpr)

		ir.OANDNOT,
		ir.OBITNOT,
		ir.OCONV,
		ir.OCONVIFACE,
		ir.OCONVNOP,
		ir.ODIV,
		ir.ODOT,
		ir.ODOTTYPE,
		ir.OLITERAL,
		ir.OLSH,
		ir.OMOD,
		ir.OMUL,
		ir.ONEG,
		ir.ONIL,
		ir.OOR,
		ir.OOROR,
		ir.OPAREN,
		ir.OPLUS,
		ir.ORSH,
		ir.OSUB,
		ir.OXOR:
		return false
	}

	// Be conservative.
	return true
}

// expand append(l1, l2...) to

	if cond.Op() == ir.OBYTES2STR && allCaseExprsAreSideEffectFree(sw) {
		cond := cond.(*ir.ConvExpr)
		cond.SetOp(ir.OBYTES2STRTMP)
	}

	cond = walkExpr(cond, sw.PtrInit())
	if cond.Op() != ir.OLITERAL && cond.Op() != ir.ONIL {
		cond = copyExpr(cond, cond.Type(), &sw.Compiled)
	}

	base.Pos = lno

	s := exprSwitch{
		pos:      lno,
		exprname: cond,
	}

	var defaultGoto ir.Node
	var body ir.Nodes

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atslaud.&3s,tniopssecca-3s,?tniopssecca-3s,?labolg-3s.tniopssecca.parm,?yasdrocsid,?t&arcomed-a-si,c&-morf,etedatad.&ecnatsni,omed,??eel&-si,rebu-si,?hgilfhtiwletoh,i:batym,,m-morf,n&atnuocca-na-si,e&duts-a-si,r-ot-ecaps,tnocresu&buhtig,e&capsppa,donil.pi,lbavresbo.citats,?kaerts,pl,???ops&edoc,golb,ppa,?s&i&hcrana-&a-si,na-si,?laicos-a-si,pareht-a-si,tra-na-si,xetn&od,seod,??oh&piym,sfn,??u&-morf,nyekcoh-asi,?v-morf,?u&-rof-slles,4,a-sppatikria,e,h,oynahtretramssi,r:ug-a-si,,?v&n-morf,rdlf,w-mo...