mirror of
https://github.com/golang/go
synced 2024-10-01 13:28:37 -06:00
6643abb26c
Suggested reading order: - doc.go - api.go, analysis.go, callgraph.go, labels.go - print.go, util.go - gen.go - solve.go - pointer_test.go, testdata/* - intrinsics.go (none are implemented yet) R=dannyb, gri, crawshaw, 0xjnml CC=golang-dev https://golang.org/cl/10618043
62 lines
1.4 KiB
Go
62 lines
1.4 KiB
Go
// +build ignore
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package main
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import "unsafe"
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var a int
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func conv1() {
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// Conversions of channel direction.
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ch := make(chan int) // @line c1make
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print((<-chan int)(ch)) // @pointsto makechan@c1make:12
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print((chan<- int)(ch)) // @pointsto makechan@c1make:12
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}
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func conv2() {
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// []byte/[]rune literal
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print([]byte("foo")) // @pointsto "foo":[]byte
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print([]rune("bar")) // @pointsto "bar":[]rune
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// string -> []byte/[]rune conversion
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s := "foo"
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ba := []byte(s) // @line c2ba
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ra := []rune(s) // @line c2ra
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print(ba) // @pointsto convert@c2ba:14
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print(ra) // @pointsto convert@c2ra:14
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}
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func conv3() {
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// Conversion of same underlying types.
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type PI *int
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pi := PI(&a)
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print(pi) // @pointsto main.a
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pint := (*int)(pi)
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print(pint) // @pointsto main.a
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// Conversions between pointers to identical base types.
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var y *PI = &pi
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var x **int = (**int)(y)
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print(*x) // @pointsto main.a
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print(*y) // @pointsto main.a
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y = (*PI)(x)
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print(*y) // @pointsto main.a
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}
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// @warning "main.conv4 contains an unsafe.Pointer conversion"
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func conv4() {
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// Handling of unsafe.Pointer conversion is unsound:
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// we lose the alias to main.a and get something like new(int) instead.
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// We require users to provide aliasing summaries.
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p := (*int)(unsafe.Pointer(&a)) // @line c2p
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print(p) // @pointsto convert@c2p:13
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}
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func main() {
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conv1()
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conv2()
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conv3()
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conv4()
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}
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