diff --git a/src/cmd/compile/internal/gc/order.go b/src/cmd/compile/internal/gc/order.go index 863de5b6c7..30e1535c09 100644 --- a/src/cmd/compile/internal/gc/order.go +++ b/src/cmd/compile/internal/gc/order.go @@ -891,7 +891,7 @@ func (o *Order) stmt(n *Node) { // c is always evaluated; x and ok are only evaluated when assigned. r.Right.Left = o.expr(r.Right.Left, nil) - if r.Right.Left.Op != ONAME { + if !r.Right.Left.IsAutoTmp() { r.Right.Left = o.copyExpr(r.Right.Left, r.Right.Left.Type, false) } diff --git a/test/fixedbugs/issue43111.go b/test/fixedbugs/issue43111.go new file mode 100644 index 0000000000..76d7beb084 --- /dev/null +++ b/test/fixedbugs/issue43111.go @@ -0,0 +1,70 @@ +// run + +// Copyright 2020 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. + +package main + +var ch chan int +var x int + +func f() int { + close(ch) + ch = nil + return 0 +} + +func g() int { + ch = nil + x = 0 + return 0 +} + +func main() { + var nilch chan int + var v int + var ok bool + _, _ = v, ok + + ch = make(chan int) + select { + case <-ch: + case nilch <- f(): + } + + ch = make(chan int) + select { + case v = <-ch: + case nilch <- f(): + } + + ch = make(chan int) + select { + case v := <-ch: _ = v + case nilch <- f(): + } + + ch = make(chan int) + select { + case v, ok = <-ch: + case nilch <- f(): + } + + ch = make(chan int) + select { + case v, ok := <-ch: _, _ = v, ok + case nilch <- f(): + } + + ch1 := make(chan int, 1) + ch = ch1 + x = 42 + select { + case ch <- x: + case nilch <- g(): + } + if got := <-ch1; got != 42 { + panic(got) + } +}