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https://github.com/golang/go
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14305527f6
The Go spec requires that select case clauses be evaluated in order, which is stricter than normal ordering semantics. cmd/compile handled this correctly for send clauses, but was not correctly handling receive clauses that involved bare variable references. Discovered with @cuonglm. Fixes #43111. Change-Id: Iec93b6514dd771875b084ba49c15d7f4531b4a6f Reviewed-on: https://go-review.googlesource.com/c/go/+/277132 Trust: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: Keith Randall <khr@golang.org>
71 lines
896 B
Go
71 lines
896 B
Go
// run
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// Copyright 2020 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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var ch chan int
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var x int
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func f() int {
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close(ch)
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ch = nil
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return 0
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}
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func g() int {
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ch = nil
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x = 0
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return 0
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}
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func main() {
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var nilch chan int
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var v int
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var ok bool
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_, _ = v, ok
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ch = make(chan int)
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select {
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case <-ch:
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case nilch <- f():
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}
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ch = make(chan int)
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select {
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case v = <-ch:
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case nilch <- f():
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}
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ch = make(chan int)
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select {
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case v := <-ch: _ = v
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case nilch <- f():
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}
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ch = make(chan int)
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select {
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case v, ok = <-ch:
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case nilch <- f():
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}
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ch = make(chan int)
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select {
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case v, ok := <-ch: _, _ = v, ok
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case nilch <- f():
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}
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ch1 := make(chan int, 1)
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ch = ch1
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x = 42
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select {
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case ch <- x:
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case nilch <- g():
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}
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if got := <-ch1; got != 42 {
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panic(got)
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}
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}
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