153 lines
2.6 KiB
Go
153 lines
2.6 KiB
Go
// +build ignore
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package main
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type I interface {
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f()
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}
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type C int
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func (*C) f() {}
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type D struct{ ptr *int }
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func (D) f() {}
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type E struct{}
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func (*E) f() {}
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var a, b int
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var unknown bool // defeat dead-code elimination
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func interface1() {
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var i interface{} = &a
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var j interface{} = D{&b}
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k := j
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if unknown {
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k = i
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}
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print(i) // @types *int
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print(j) // @types D
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print(k) // @types *int | D
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print(i.(*int)) // @pointsto main.a
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print(j.(*int)) // @pointsto
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print(k.(*int)) // @pointsto main.a
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print(i.(D).ptr) // @pointsto
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print(j.(D).ptr) // @pointsto main.b
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print(k.(D).ptr) // @pointsto main.b
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}
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func interface2() {
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var i I = (*C)(&a)
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var j I = D{&a}
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k := j
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if unknown {
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k = i
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}
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print(i) // @types *C
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print(j) // @types D
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print(k) // @types *C | D
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print(k) // @pointsto makeinterface:main.D | makeinterface:*main.C
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k.f()
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// @calls main.interface2 -> (*main.C).f
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// @calls main.interface2 -> (main.D).f
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print(i.(*C)) // @pointsto main.a
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print(j.(D).ptr) // @pointsto main.a
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print(k.(*C)) // @pointsto main.a
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switch x := k.(type) {
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case *C:
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print(x) // @pointsto main.a
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case D:
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print(x.ptr) // @pointsto main.a
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case *E:
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print(x) // @pointsto
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}
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}
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func interface3() {
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// There should be no backflow of concrete types from the type-switch to x.
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var x interface{} = 0
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print(x) // @types int
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switch x.(type) {
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case int:
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case string:
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}
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}
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func interface4() {
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var i interface{} = D{&a}
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if unknown {
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i = 123
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}
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print(i) // @types int | D
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j := i.(I) // interface narrowing type-assertion
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print(j) // @types D
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print(j.(D).ptr) // @pointsto main.a
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var l interface{} = j // interface widening assignment.
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print(l) // @types D
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print(l.(D).ptr) // @pointsto main.a
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m := j.(interface{}) // interface widening type-assertion.
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print(m) // @types D
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print(m.(D).ptr) // @pointsto main.a
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}
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// Interface method calls and value flow:
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type J interface {
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f(*int) *int
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}
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type P struct {
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x int
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}
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func (p *P) f(pi *int) *int {
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print(p) // @pointsto p@i5p:6
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print(pi) // @pointsto i@i5i:6
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return &p.x
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}
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func interface5() {
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var p P // @line i5p
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var j J = &p
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var i int // @line i5i
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print(j.f(&i)) // @pointsto p.x@i5p:6
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print(&i) // @pointsto i@i5i:6
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print(j) // @pointsto makeinterface:*main.P
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}
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// @calls main.interface5 -> (*main.P).f
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func interface6() {
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f := I.f
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print(f) // @pointsto (main.I).f$thunk
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f(new(struct{ D }))
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}
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// @calls main.interface6 -> (main.I).f$thunk
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// @calls (main.I).f$thunk -> (*struct{main.D}).f
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func main() {
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interface1()
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interface2()
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interface3()
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interface4()
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interface5()
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interface6()
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}
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