F2(i, i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"
	F3() (i, i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"
}

type T1 func(i, i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"
type T2 func(i int) (i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"

	F2(i, i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"
	F3() (i, i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"
}

var T1 func(i, i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"
var T2 func(i int) (i int) // ERROR "duplicate argument i|redefinition|previous|redeclared"

	{
		// simple redeclaration
		i := f1()
		i := f1() // ERROR "redeclared|no new"
		_ = i
	}
	{
		// change of type for f
		i, f, s := f3()
		f, g, t := f3() // ERROR "redeclared|cannot assign|incompatible|cannot use"
		_, _, _, _, _ = i, f, s, g, t
	}
	{
		// change of type for i
		i, f, s := f3()
		j, i, t := f3() // ERROR "redeclared|cannot assign|incompatible|cannot use"
		_, _, _, _, _ = i, f, s, j, t
	}

	F2 func(x, y, z float32)
	F3 func(x, y, x /* ERROR "redeclared" */ float32)
	F4 func() (x, y, x /* ERROR "redeclared" */ float32)
	F5 func(x int) (x /* ERROR "redeclared" */ float32)
	F6 func(x ...int)

	I1 interface{}
	I2 interface {
		m1()
	}
	I3 interface {
		m1()
		m1 /* ERROR "duplicate method m1" */ ()
	}
	I4 interface {
		m1(x, y, x /* ERROR "redeclared" */ float32)

const pi = 3.1415

func (T1) m /* ERROR "already declared" */ () {}
func (T2) m(io.Writer) {}

type T3 struct {
	f *T3
}

type T6 struct {
	x int
}

func (t *T6) m1() int {
	return t.x
}

func f() {
	var t *T6
	t.m1()
}

// Double declarations across package files
const c_double /* ERROR "redeclared" */ = 0
type t_double  /* ERROR "redeclared" */ int
var v_double /* ERROR "redeclared" */ int

func (t *T) M(int, float64) {} // ERROR "already declared|redefinition"

func (t T) H()  // GCCGO_ERROR "previous"
func (t *T) H() {} // ERROR "already declared|redefinition"

func f(int, string)  // GCCGO_ERROR "previous"
func f(int, float64) {} // ERROR "redeclared|redefinition"

func g(a int, b string) // GCCGO_ERROR "previous"

func _(f int) {
}

// 2
var g byte

func _(g int) {
}

var g interface{} // ERROR "issue20415.go:20: previous declaration|redefinition|g redeclared"

// 3
func _(h int) {
}

var h byte

// A package that redeclares common builtin names.
package a

var true = 0 == 1
var false = 0 == 0
var nil = 1

const append = 42

type error bool
type int interface{}

func len(interface{}) int32 { return 42 }

func Test() {
	var array [append]int
	if true {
		panic("unexpected builtin true instead of redeclared one")
	}
	if !false {

package tparam1

// The predeclared identifier "any" may be used in place of interface{}.
var _ any

func _(_ any)

type _[_ any] struct{}

const N = 10

type (
	_                     []struct{}  // slice
	_                     [N]struct{} // array
	_[T any]              struct{}
	_[T, T any]           struct{} // ERROR "T redeclared"
	_[T1, T2 any, T3 any] struct{}
)

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

TEXT foo(SB), 0, $0
	RET
TEXT foo(SB), 0, $0 // ERROR "symbol foo redeclared"
	RET

GLOBL bar(SB), 0, $8
GLOBL bar(SB), 0, $8 // ERROR "symbol bar redeclared"

DATA bar+0(SB)/8, $0