// hasDots reports whether the last argument in the call is followed by ...
func hasDots(call *syntax.CallExpr) bool { return call.HasDots }

// dddErrPos returns the node (poser) for reporting an invalid ... use in a call.
func dddErrPos(call *syntax.CallExpr) *syntax.CallExpr {
	// TODO(gri) should use "..." instead of call position
	return call
}

func fixAtPosCall(f *ast.File) {
	ast.Inspect(f, func(n ast.Node) bool {
		switch n := n.(type) {
		case *ast.CallExpr:
			if selx, _ := n.Fun.(*ast.SelectorExpr); selx != nil && selx.Sel.Name == "dump" {
				for i, arg := range n.Args {
					if call, _ := arg.(*ast.CallExpr); call != nil {
						// rewrite xxx.dump(..., atPos(x), ...) to xxx.dump(..., x.Pos(), ...)
						if isIdent(call.Fun, "atPos") {

func hasDots(call *ast.CallExpr) bool { return call.Ellipsis.IsValid() }

// dddErrPos returns the positioner for reporting an invalid ... use in a call.
func dddErrPos(call *ast.CallExpr) positioner { return atPos(call.Ellipsis) }

// argErrPos returns positioner for reporting an invalid argument count.
func argErrPos(call *ast.CallExpr) positioner { return inNode(call, call.Rparen) }

	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)

	nodeFilter := []ast.Node{
		(*ast.CallExpr)(nil),
		(*ast.StarExpr)(nil),
		(*ast.UnaryExpr)(nil),
	}
	inspect.Preorder(nodeFilter, func(n ast.Node) {
		switch x := n.(type) {
		case *ast.CallExpr:
			if len(x.Args) == 1 &&
				hasBasicType(pass.TypesInfo, x.Fun, types.UnsafePointer) &&

		(*ast.FuncDecl)(nil),
		(*ast.GoStmt)(nil),
		(*ast.CallExpr)(nil),
	}, func(node ast.Node, push bool) bool {
		if !push {
			return false
		}
		switch node := node.(type) {
		case *ast.FuncDecl:
			return hasBenchmarkOrTestParams(node)

		case *ast.GoStmt:
			c := goAsyncCall(pass.TypesInfo, node, toDecl)
			addCall(c)

		case *ast.CallExpr:
			c := tRunAsyncCall(pass.TypesInfo, node)
			addCall(c)
		}

		base.Fatalf("vmkcall %v needs %v args got %v", fn, n, len(va))
	}

	call := typecheck.Call(base.Pos, fn, va, false).(*ir.CallExpr)
	call.SetType(t)
	return walkExpr(call, init).(*ir.CallExpr)
}

func mkcall(name string, t *types.Type, init *ir.Nodes, args ...ir.Node) *ir.CallExpr {
	return vmkcall(typecheck.LookupRuntime(name), t, init, args)
}

func mkcallstmt(name string, args ...ir.Node) ir.Node {

	x = astutil.Unparen(x) // ignore parens on rhs

	if _, ok := x.(*ast.CompositeLit); ok {
		return nil
	}
	if _, ok := x.(*ast.CallExpr); ok {
		// A call may return a zero value.
		return nil
	}
	if star, ok := x.(*ast.StarExpr); ok {
		if _, ok := astutil.Unparen(star.X).(*ast.CallExpr); ok {
			// A call may return a pointer to a zero value.
			return nil
		}
	}

	// skip the traversal.
	if !analysisutil.Imports(pass.Pkg, "net/http") {
		return nil, nil
	}

	nodeFilter := []ast.Node{
		(*ast.CallExpr)(nil),
	}
	inspect.WithStack(nodeFilter, func(n ast.Node, push bool, stack []ast.Node) bool {
		if !push {
			return true
		}
		call := n.(*ast.CallExpr)
		if !isHTTPFuncOrMethodOnClient(pass.TypesInfo, call) {
			return true // the function call is not related to this check.
		}

	// TODO(taking): Consider using a prepass to collect typeutil.Callees.

	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)

	nodeFilter := []ast.Node{
		(*ast.CallExpr)(nil),
	}
	inspect.Preorder(nodeFilter, func(n ast.Node) {
		call := n.(*ast.CallExpr)
		fn := typeutil.StaticCallee(pass.TypesInfo, call)
		if fn == nil {
			return // not a static call
		}

		// Classify the callee (without allocating memory).

		return tcClose(n)

	case ir.ODELETE:
		n := n.(*ir.CallExpr)
		return tcDelete(n)

	case ir.OAPPEND:
		n := n.(*ir.CallExpr)
		return tcAppend(n)

	case ir.OCOPY:
		n := n.(*ir.BinaryExpr)
		return tcCopy(n)

	case ir.OCONV:
		n := n.(*ir.ConvExpr)
		return tcConv(n)

	case ir.OMAKE:
		n := n.(*ir.CallExpr)
		return tcMake(n)

	case ir.ONEW:
		n := n.(*ir.UnaryExpr)