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// run
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Issue 4585: comparisons and hashes process blank
// fields and padding in structs.
package main
import "unsafe"
// T is a structure with padding.
type T struct {
A int16
B int64
C int16
D int64
Dummy [64]byte
}
// U is a structure with a blank field
type U struct {
A, _, B int
Dummy [64]byte
}
// USmall is like U but the frontend will inline comparison
// instead of calling the generated eq function.
type USmall struct {
A, _, B int32
}
// V has padding but not on the first field.
type V struct {
A1, A2, A3 int32
B int16
C int32
}
// W has padding at the end.
type W struct {
A1, A2, A3 int32
B int32
C int8
}
func test1() {
var a, b U
m := make(map[U]int)
copy((*[16]byte)(unsafe.Pointer(&a))[:], "hello world!")
a.A, a.B = 1, 2
b.A, b.B = 1, 2
if a != b {
panic("broken equality: a != b")
}
m[a] = 1
m[b] = 2
if len(m) == 2 {
panic("broken hash: len(m) == 2")
}
if m[a] != 2 {
panic("m[a] != 2")
}
}
func test2() {
var a, b T
m := make(map[T]int)
copy((*[16]byte)(unsafe.Pointer(&a))[:], "hello world!")
a.A, a.B, a.C, a.D = 1, 2, 3, 4
b.A, b.B, b.C, b.D = 1, 2, 3, 4
if a != b {
panic("broken equality: a != b")
}
m[a] = 1
m[b] = 2
if len(m) == 2 {
panic("broken hash: len(m) == 2")
}
if m[a] != 2 {
panic("m[a] != 2")
}
}
func test3() {
var a, b USmall
copy((*[12]byte)(unsafe.Pointer(&a))[:], "hello world!")
a.A, a.B = 1, 2
b.A, b.B = 1, 2
if a != b {
panic("broken equality: a != b")
}
}
func test4() {
var a, b V
m := make(map[V]int)
copy((*[20]byte)(unsafe.Pointer(&a))[:], "Hello World, Gopher!")
a.A1, a.A2, a.A3, a.B, a.C = 1, 2, 3, 4, 5
b.A1, b.A2, b.A3, b.B, b.C = 1, 2, 3, 4, 5
if a != b {
panic("broken equality: a != b")
}
m[a] = 1
m[b] = 2
if len(m) == 2 {
panic("broken hash: len(m) == 2")
}
if m[a] != 2 {
panic("m[a] != 2")
}
}
func test5() {
var a, b W
m := make(map[W]int)
copy((*[20]byte)(unsafe.Pointer(&a))[:], "Hello World, Gopher!")
a.A1, a.A2, a.A3, a.B, a.C = 1, 2, 3, 4, 5
b.A1, b.A2, b.A3, b.B, b.C = 1, 2, 3, 4, 5
if a != b {
panic("broken equality: a != b")
}
m[a] = 1
m[b] = 2
if len(m) == 2 {
panic("broken hash: len(m) == 2")
}
if m[a] != 2 {
panic("m[a] != 2")
}
}
func main() {
test1()
test2()
test3()
test4()
test5()
}
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