}
		fmt.Fprintf(s, ".%s", n.Sel.Name)

	case ODOTTYPE, ODOTTYPE2:
		n := n.(*TypeAssertExpr)
		exprFmt(n.X, s, nprec)
		fmt.Fprintf(s, ".(%v)", n.Type())

	case OINDEX, OINDEXMAP:
		n := n.(*IndexExpr)
		exprFmt(n.X, s, nprec)
		fmt.Fprintf(s, "[%v]", n.Index)

	case OSLICE, OSLICESTR, OSLICEARR, OSLICE3, OSLICE3ARR:
		n := n.(*SliceExpr)
		exprFmt(n.X, s, nprec)
		fmt.Fprint(s, "[")

			if t.Op != syntax.Mul || t.Y != nil {
				break
			}
			ptr = true
			rtyp = t.X
		default:
			break L
		}
	}

	// unpack type parameters, if any
	if ptyp, _ := rtyp.(*syntax.IndexExpr); ptyp != nil {
		rtyp = ptyp.X
		if unpackParams {
			for _, arg := range syntax.UnpackListExpr(ptyp.Index) {
				var par *syntax.Name
				switch arg := arg.(type) {
				case *syntax.Name:
					par = arg

		case *ast.ParenExpr:
			rtyp = t.X
		case *ast.StarExpr:
			ptr = true
			rtyp = t.X
		default:
			break L
		}
	}

	// unpack type parameters, if any
	switch rtyp.(type) {
	case *ast.IndexExpr, *ast.IndexListExpr:
		ix := typeparams.UnpackIndexExpr(rtyp)
		rtyp = ix.X
		if unpackParams {
			for _, arg := range ix.Indices {
				var par *ast.Ident
				switch arg := arg.(type) {
				case *ast.Ident:

	}
	if !t.IsInterface() {
		base.Fatalf("OITAB of %v", t)
	}
	n.SetType(types.NewPtr(types.Types[types.TUINTPTR]))
	return n
}

// tcIndex typechecks an OINDEX node.
func tcIndex(n *ir.IndexExpr) ir.Node {
	n.X = Expr(n.X)
	n.X = DefaultLit(n.X, nil)
	n.X = implicitstar(n.X)
	l := n.X
	n.Index = Expr(n.Index)
	r := n.Index
	t := l.Type()
	if t == nil || r.Type() == nil {
		n.SetType(nil)

		p.setPos(x.Rparen)
		p.print(token.RPAREN)

	case *ast.IndexExpr:
		// TODO(gri): should treat[] like parentheses and undo one level of depth
		p.expr1(x.X, token.HighestPrec, 1)
		p.setPos(x.Lbrack)
		p.print(token.LBRACK)
		p.expr0(x.Index, depth+1)
		p.setPos(x.Rbrack)
		p.print(token.RBRACK)

	case *ast.IndexListExpr:
		// TODO(gri): as for IndexExpr, should treat [] like parentheses and undo
		// one level of depth

	case ir.ODOT:
		n := n.(*ir.SelectorExpr)
		if name, offset, ok = StaticLoc(n.X); !ok {
			break
		}
		offset += n.Offset()
		return name, offset, true

	case ir.OINDEX:
		n := n.(*ir.IndexExpr)
		if n.X.Type().IsSlice() {
			break
		}
		if name, offset, ok = StaticLoc(n.X); !ok {
			break
		}
		l := getlit(n.Index)
		if l < 0 {
			break
		}

		// Check for overflow.

			s.assign(left.X, new, false, 0)
			// TODO: do we need to update named values here?
			return
		}
		if left.Op() == ir.OINDEX && left.(*ir.IndexExpr).X.Type().IsArray() {
			left := left.(*ir.IndexExpr)
			s.pushLine(left.Pos())
			defer s.popLine()
			// We're assigning to an element of an ssa-able array.
			// a[i] = v
			t := left.X.Type()
			n := t.NumElem()

		if !p.isType(c.Fun) && !p.isUnsafeData(c.Fun, false) {
			break
		}
		x = c.Args[0]
	}
	u, ok := x.(*ast.UnaryExpr)
	if !ok || u.Op != token.AND {
		return false
	}
	index, ok := u.X.(*ast.IndexExpr)
	if !ok {
		return false
	}

	addr := ""
	deref := ""
	if p.isVariable(index.X) {
		addr = "&"
		deref = "*"
	}

	case *ast.UnaryExpr:
		u.node(node.X)
	case *ast.BinaryExpr:
		u.node(node.X)
		u.node(node.Y)
	case *ast.StarExpr:
		u.node(node.X)
	case *ast.ParenExpr:
		u.node(node.X)
	case *ast.IndexExpr:
		u.node(node.X)
		u.node(node.Index)
	case *ast.TypeAssertExpr:
		u.node(node.X)
		u.node(node.Type)
	case *ast.Ident:
		if obj := u.scope.Lookup(node.Name); obj != nil {
			obj.numUses++

		{"IncDecStmt", Type, 0},
		{"IncDecStmt.Tok", Field, 0},
		{"IncDecStmt.TokPos", Field, 0},
		{"IncDecStmt.X", Field, 0},
		{"IndexExpr", Type, 0},
		{"IndexExpr.Index", Field, 0},
		{"IndexExpr.Lbrack", Field, 0},
		{"IndexExpr.Rbrack", Field, 0},
		{"IndexExpr.X", Field, 0},
		{"IndexListExpr", Type, 18},
		{"IndexListExpr.Indices", Field, 18},
		{"IndexListExpr.Lbrack", Field, 18},