go runtime_error ai_generated true

panic: sync: WaitGroup 在之前的 Wait 返回前被重用

panic: sync: WaitGroup is reused before previous Wait has returned

ID: go/waitgroup-misused-copy

其他格式: JSON · Markdown 中文 · English

80%修复率

90%置信度

0证据数

2024-05-21首次发现

版本兼容性

版本	状态	引入	弃用	备注
1.20	active	—	—	—
1.23	active	—	—	—

根因分析

在另一个 goroutine 仍处于 wg.Wait 时再次调用 wg.Add。通常发生在循环中跨迭代复用同一个 WaitGroup 而未重置。

English

wg.Add called again while another goroutine is still in wg.Wait. Typically happens with a loop that reuses the same WaitGroup across iterations without resetting.

generic

解决方案

95% 成功率

for _, batch := range batches {
    var wg sync.WaitGroup
    for _, x := range batch {
        wg.Add(1)
        go func(x int) { defer wg.Done(); work(x) }(x)
    }
    wg.Wait()
}

93% 成功率

for _, batch := range batches {
    g := new(errgroup.Group)
    for _, x := range batch { x := x; g.Go(func() error { return work(x) }) }
    if err := g.Wait(); err != nil { return err }
}

无效尝试

常见但无效的做法:

85% 失败
Reassigning while Wait is in flight races on the struct; still panics or corrupts state.
80% 失败
Sleep does not synchronize with Wait's completion; race remains.