diff --git a/src/cmd/compile/internal/noder/writer.go b/src/cmd/compile/internal/noder/writer.go index 641374e03c4..87c54b97694 100644 --- a/src/cmd/compile/internal/noder/writer.go +++ b/src/cmd/compile/internal/noder/writer.go @@ -1217,10 +1217,17 @@ func (w *writer) stmt(stmt syntax.Stmt) { func (w *writer) stmts(stmts []syntax.Stmt) { dead := false w.Sync(pkgbits.SyncStmts) - for _, stmt := range stmts { - if dead { - // Any statements after a terminating statement are safe to - // omit, at least until the next labeled statement. + var lastLabel = -1 + for i, stmt := range stmts { + if _, ok := stmt.(*syntax.LabeledStmt); ok { + lastLabel = i + } + } + for i, stmt := range stmts { + if dead && i > lastLabel { + // Any statements after a terminating and last label statement are safe to omit. + // Otherwise, code after label statement may refer to dead stmts between terminating + // and label statement, see issue #65593. if _, ok := stmt.(*syntax.LabeledStmt); !ok { continue } diff --git a/test/fixedbugs/issue65593.go b/test/fixedbugs/issue65593.go new file mode 100644 index 00000000000..892a78122ee --- /dev/null +++ b/test/fixedbugs/issue65593.go @@ -0,0 +1,21 @@ +// compile + +// Copyright 2024 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 p + +const run = false + +func f() { + if !run { + return + } + + messages := make(chan struct{}, 1) +main: + for range messages { + break main + } +}