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package testdata
import (
"sync"
"sync/atomic"
"unsafe"
. "unsafe"
unsafe1 "unsafe"
)
func OkFunc() {
var x *sync.Mutex
p := x
var y sync.Mutex
p = &y
var z = sync.Mutex{}
w := sync.Mutex{}
w = sync.Mutex{}
q := struct{ L sync.Mutex }{
L: sync.Mutex{},
}
yy := []Tlock{
Tlock{},
Tlock{
once: sync.Once{},
},
}
nl := new(sync.Mutex)
mx := make([]sync.Mutex, 10)
xx := struct{ L *sync.Mutex }{
L: new(sync.Mutex),
}
}
type Tlock struct {
once sync.Once
}
func BadFunc() {
var x *sync.Mutex
p := x
var y sync.Mutex
p = &y
*p = *x // ERROR "assignment copies lock value to \*p: sync.Mutex"
var t Tlock
var tp *Tlock
tp = &t
*tp = t // ERROR "assignment copies lock value to \*tp: testdata.Tlock contains sync.Once contains sync.Mutex"
t = *tp // ERROR "assignment copies lock value to t: testdata.Tlock contains sync.Once contains sync.Mutex"
y := *x // ERROR "assignment copies lock value to y: sync.Mutex"
var z = t // ERROR "variable declaration copies lock value to z: testdata.Tlock contains sync.Once contains sync.Mutex"
w := struct{ L sync.Mutex }{
L: *x, // ERROR "literal copies lock value from \*x: sync.Mutex"
}
var q = map[int]Tlock{
1: t, // ERROR "literal copies lock value from t: testdata.Tlock contains sync.Once contains sync.Mutex"
2: *tp, // ERROR "literal copies lock value from \*tp: testdata.Tlock contains sync.Once contains sync.Mutex"
}
yy := []Tlock{
t, // ERROR "literal copies lock value from t: testdata.Tlock contains sync.Once contains sync.Mutex"
*tp, // ERROR "literal copies lock value from \*tp: testdata.Tlock contains sync.Once contains sync.Mutex"
}
// override 'new' keyword
new := func(interface{}) {}
new(t) // ERROR "call of new copies lock value: testdata.Tlock contains sync.Once contains sync.Mutex"
// copy of array of locks
var muA [5]sync.Mutex
muB := muA // ERROR "assignment copies lock value to muB: sync.Mutex"
muA = muB // ERROR "assignment copies lock value to muA: sync.Mutex"
muSlice := muA[:] // OK
// multidimensional array
var mmuA [5][5]sync.Mutex
mmuB := mmuA // ERROR "assignment copies lock value to mmuB: sync.Mutex"
mmuA = mmuB // ERROR "assignment copies lock value to mmuA: sync.Mutex"
mmuSlice := mmuA[:] // OK
// slice copy is ok
var fmuA [5][][5]sync.Mutex
fmuB := fmuA // OK
fmuA = fmuB // OK
fmuSlice := fmuA[:] // OK
}
func LenAndCapOnLockArrays() {
var a [5]sync.Mutex
aLen := len(a) // OK
aCap := cap(a) // OK
// override 'len' and 'cap' keywords
len := func(interface{}) {}
len(a) // ERROR "call of len copies lock value: sync.Mutex"
cap := func(interface{}) {}
cap(a) // ERROR "call of cap copies lock value: sync.Mutex"
}
func SizeofMutex() {
var mu sync.Mutex
unsafe.Sizeof(mu) // OK
unsafe1.Sizeof(mu) // OK
Sizeof(mu) // OK
unsafe := struct{ Sizeof func(interface{}) }{}
unsafe.Sizeof(mu) // ERROR "call of unsafe.Sizeof copies lock value: sync.Mutex"
Sizeof := func(interface{}) {}
Sizeof(mu) // ERROR "call of Sizeof copies lock value: sync.Mutex"
}
// SyncTypesCheck checks copying of sync.* types except sync.Mutex
func SyncTypesCheck() {
// sync.RWMutex copying
var rwmuX sync.RWMutex
var rwmuXX = sync.RWMutex{}
rwmuX1 := new(sync.RWMutex)
rwmuY := rwmuX // ERROR "assignment copies lock value to rwmuY: sync.RWMutex"
rwmuY = rwmuX // ERROR "assignment copies lock value to rwmuY: sync.RWMutex"
var rwmuYY = rwmuX // ERROR "variable declaration copies lock value to rwmuYY: sync.RWMutex"
rwmuP := &rwmuX
rwmuZ := &sync.RWMutex{}
// sync.Cond copying
var condX sync.Cond
var condXX = sync.Cond{}
condX1 := new(sync.Cond)
condY := condX // ERROR "assignment copies lock value to condY: sync.Cond contains sync.noCopy"
condY = condX // ERROR "assignment copies lock value to condY: sync.Cond contains sync.noCopy"
var condYY = condX // ERROR "variable declaration copies lock value to condYY: sync.Cond contains sync.noCopy"
condP := &condX
condZ := &sync.Cond{
L: &sync.Mutex{},
}
condZ = sync.NewCond(&sync.Mutex{})
// sync.WaitGroup copying
var wgX sync.WaitGroup
var wgXX = sync.WaitGroup{}
wgX1 := new(sync.WaitGroup)
wgY := wgX // ERROR "assignment copies lock value to wgY: sync.WaitGroup contains sync.noCopy"
wgY = wgX // ERROR "assignment copies lock value to wgY: sync.WaitGroup contains sync.noCopy"
var wgYY = wgX // ERROR "variable declaration copies lock value to wgYY: sync.WaitGroup contains sync.noCopy"
wgP := &wgX
wgZ := &sync.WaitGroup{}
// sync.Pool copying
var poolX sync.Pool
var poolXX = sync.Pool{}
poolX1 := new(sync.Pool)
poolY := poolX // ERROR "assignment copies lock value to poolY: sync.Pool contains sync.noCopy"
poolY = poolX // ERROR "assignment copies lock value to poolY: sync.Pool contains sync.noCopy"
var poolYY = poolX // ERROR "variable declaration copies lock value to poolYY: sync.Pool contains sync.noCopy"
poolP := &poolX
poolZ := &sync.Pool{}
// sync.Once copying
var onceX sync.Once
var onceXX = sync.Once{}
onceX1 := new(sync.Once)
onceY := onceX // ERROR "assignment copies lock value to onceY: sync.Once contains sync.Mutex"
onceY = onceX // ERROR "assignment copies lock value to onceY: sync.Once contains sync.Mutex"
var onceYY = onceX // ERROR "variable declaration copies lock value to onceYY: sync.Once contains sync.Mutex"
onceP := &onceX
onceZ := &sync.Once{}
}
// AtomicTypesCheck checks copying of sync/atomic types
func AtomicTypesCheck() {
// atomic.Value copying
var vX atomic.Value
var vXX = atomic.Value{}
vX1 := new(atomic.Value)
// These are OK because the value has not been used yet.
// (And vet can't tell whether it has been used, so they're always OK.)
vY := vX
vY = vX
var vYY = vX
vP := &vX
vZ := &atomic.Value{}
}
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