nodeFilter := []ast.Node{
		(*ast.CallExpr)(nil),
	}
	inspect.Preorder(nodeFilter, func(n ast.Node) {
		call := n.(*ast.CallExpr)
		if !isSignalNotify(pass.TypesInfo, call) {
			return
		}
		var chanDecl *ast.CallExpr
		switch arg := call.Args[0].(type) {
		case *ast.Ident:
			if decl, ok := findDecl(arg).(*ast.CallExpr); ok {
				chanDecl = decl
			}
		case *ast.CallExpr:

	"golang.org/x/tools/internal/typeparams"
)

// Callee returns the named target of a function call, if any:
// a function, method, builtin, or variable.
//
// Functions and methods may potentially have type parameters.
func Callee(info *types.Info, call *ast.CallExpr) types.Object {
	fun := astutil.Unparen(call.Fun)

	// Look through type instantiation if necessary.
	isInstance := false
	switch fun.(type) {

	nodeFilter := []ast.Node{
		(*ast.CallExpr)(nil),
	}
	inspect.Preorder(nodeFilter, func(node ast.Node) {
		call := node.(*ast.CallExpr)
		fn := typeutil.StaticCallee(pass.TypesInfo, call)
		if fn == nil {
			return // not a static call
		}
		if call.Ellipsis != token.NoPos {
			return // skip calls with "..." args
		}
		skipArgs, ok := kvFuncSkipArgs(fn)
		if !ok {

	nodeFilter := []ast.Node{
		(*ast.CallExpr)(nil),
	}
	inspect.Preorder(nodeFilter, func(n ast.Node) {
		call := n.(*ast.CallExpr)
		b, ok := typeutil.Callee(pass.TypesInfo, call).(*types.Builtin)
		if ok && b.Name() == "append" && len(call.Args) == 1 {
			pass.ReportRangef(call, "append with no values")
		}
	})

	return nil, nil

const (
	// No info about this param
	ParamNoInfo ParamPropBits = 0

	// Parameter value feeds unmodified into a top-level interface
	// call (this assumes the parameter is of interface type).
	ParamFeedsInterfaceMethodCall ParamPropBits = 1 << iota

	// Parameter value feeds unmodified into an interface call that
	// may be conditional/nested and not always executed (this assumes
	// the parameter is of interface type).

	// Only valid on functions that declare a frame size of 0.
	// TODO(mwhudson): only implemented for ppc64x at present.
	NOFRAME = 512

	// Function can call reflect.Type.Method or reflect.Type.MethodByName.
	REFLECTMETHOD = 1024

	// Function is the outermost frame of the call stack. Call stack unwinders
	// should stop at this function.
	TOPFRAME = 2048

	// Function is an ABI wrapper.
	ABIWRAPPER = 4096

// implementations of AES should implement their
// own version of newCipher (which may then call
// newCipherGeneric if needed).
func newCipher(key []byte) (cipher.Block, error) {
	return newCipherGeneric(key)
}

// expandKey is used by BenchmarkExpand and should
// call an assembly implementation if one is available.
func expandKey(key []byte, enc, dec []uint32) {
	expandKeyGo(key, enc, dec)

	return unveil(nil, nil)
}

// supportsUnveil checks for availability of the unveil(2) system call based
// on the running OpenBSD version.
func supportsUnveil() error {
	maj, min, err := majmin()
	if err != nil {
		return err
	}

	// unveil is not available before 6.4
	if maj < 6 || (maj == 6 && min <= 3) {
		return fmt.Errorf("cannot call Unveil on OpenBSD %d.%d", maj, min)
	}

	return nil

				add(ifStart)
				end = ifEnd
			}
		default:
			// check that nothing under this contains a putattr call
			ast.Inspect(stmt, func(n ast.Node) bool {
				if call, _ := n.(*ast.CallExpr); call != nil {
					if exprToString(call.Fun) == "putattr" {
						t.Fatalf("%s use of putattr in unsupported block", fset.Position(call.Pos()))
					}
				}
				return true
			})
		}
	}
	return start, end
}

		Context: context,
	})
}

// Save calls to C.xxx for later processing.
func (f *File) saveCall(call *ast.CallExpr, context astContext) {
	sel, ok := call.Fun.(*ast.SelectorExpr)
	if !ok {
		return
	}
	if l, ok := sel.X.(*ast.Ident); !ok || l.Name != "C" {
		return
	}
	c := &Call{Call: call, Deferred: context == ctxDefer}
	f.Calls = append(f.Calls, c)
}