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// errorcheck -0 -N -d=nil
// 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.
// Test that nil checks are inserted.
// Optimization is disabled, so redundant checks are not removed.
package p
type Struct struct {
X int
Y float64
}
type BigStruct struct {
X int
Y float64
A [1 << 20]int
Z string
}
type Empty struct {
}
type Empty1 struct {
Empty
}
var (
intp *int
arrayp *[10]int
array0p *[0]int
bigarrayp *[1 << 26]int
structp *Struct
bigstructp *BigStruct
emptyp *Empty
empty1p *Empty1
)
func f1() {
_ = *intp // ERROR "nil check"
_ = *arrayp // ERROR "nil check"
_ = *array0p // ERROR "nil check"
_ = *array0p // ERROR "nil check"
_ = *intp // ERROR "nil check"
_ = *arrayp // ERROR "nil check"
_ = *structp // ERROR "nil check"
_ = *emptyp // ERROR "nil check"
_ = *arrayp // ERROR "nil check"
}
func f2() {
var (
intp *int
arrayp *[10]int
array0p *[0]int
bigarrayp *[1 << 20]int
structp *Struct
bigstructp *BigStruct
emptyp *Empty
empty1p *Empty1
)
_ = *intp // ERROR "nil check"
_ = *arrayp // ERROR "nil check"
_ = *array0p // ERROR "nil check"
_ = *array0p // ERROR "nil check"
_ = *intp // ERROR "nil check"
_ = *arrayp // ERROR "nil check"
_ = *structp // ERROR "nil check"
_ = *emptyp // ERROR "nil check"
_ = *arrayp // ERROR "nil check"
_ = *bigarrayp // ERROR "nil check"
_ = *bigstructp // ERROR "nil check"
_ = *empty1p // ERROR "nil check"
}
func fx10k() *[10000]int
var b bool
func f3(x *[10000]int) {
// Using a huge type and huge offsets so the compiler
// does not expect the memory hardware to fault.
_ = x[9999] // ERROR "nil check"
for {
if x[9999] != 0 { // ERROR "nil check"
break
}
}
x = fx10k()
_ = x[9999] // ERROR "nil check"
if b {
_ = x[9999] // ERROR "nil check"
} else {
_ = x[9999] // ERROR "nil check"
}
_ = x[9999] // ERROR "nil check"
x = fx10k()
if b {
_ = x[9999] // ERROR "nil check"
} else {
_ = x[9999] // ERROR "nil check"
}
_ = x[9999] // ERROR "nil check"
fx10k()
// This one is a bit redundant, if we figured out that
// x wasn't going to change across the function call.
// But it's a little complex to do and in practice doesn't
// matter enough.
_ = x[9999] // ERROR "nil check"
}
func f3a() {
x := fx10k()
y := fx10k()
z := fx10k()
_ = &x[9] // ERROR "nil check"
y = z
_ = &x[9] // ERROR "nil check"
x = y
_ = &x[9] // ERROR "nil check"
}
func f3b() {
x := fx10k()
y := fx10k()
_ = &x[9] // ERROR "nil check"
y = x
_ = &x[9] // ERROR "nil check"
x = y
_ = &x[9] // ERROR "nil check"
}
func fx10() *[10]int
func f4(x *[10]int) {
// Most of these have no checks because a real memory reference follows,
// and the offset is small enough that if x is nil, the address will still be
// in the first unmapped page of memory.
_ = x[9] // ERROR "nil check"
for {
if x[9] != 0 { // ERROR "nil check"
break
}
}
x = fx10()
_ = x[9] // ERROR "nil check"
if b {
_ = x[9] // ERROR "nil check"
} else {
_ = x[9] // ERROR "nil check"
}
_ = x[9] // ERROR "nil check"
x = fx10()
if b {
_ = x[9] // ERROR "nil check"
} else {
_ = &x[9] // ERROR "nil check"
}
_ = x[9] // ERROR "nil check"
fx10()
_ = x[9] // ERROR "nil check"
x = fx10()
y := fx10()
_ = &x[9] // ERROR "nil check"
y = x
_ = &x[9] // ERROR "nil check"
x = y
_ = &x[9] // ERROR "nil check"
}
func f5(m map[string]struct{}) bool {
// Existence-only map lookups should not generate a nil check
_, ok := m[""]
return ok
}
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