go runtime_error ai_generated true

panic: sync: WaitGroup 计数器为负

panic: sync: negative WaitGroup counter

ID: go/negative-waitgroup-counter

其他格式: JSON · Markdown 中文 · English
80%修复率
90%置信度
0证据数
2024-04-15首次发现

版本兼容性

版本状态引入弃用备注
1.x active — — —

根因分析

wg.Done() 调用次数多于 wg.Add(n)。常见于在迭代次数多于 Add 的循环中 defer Done，或有 goroutine 调用 Done 却没有匹配的 Add。

English

wg.Done() is called more times than wg.Add(n). Common when Done is deferred in a loop that runs more iterations than Add, or a goroutine calls Done without a matching Add.

generic

解决方案

  1. 95% 成功率 
    Call Add(1) synchronously before launching each goroutine and defer Done inside:
for _, item := range items {
    wg.Add(1)
    go func(it Item){ defer wg.Done(); process(it) }(item)
}
wg.Wait()
  2. 92% 成功率 
    Use golang.org/x/sync/errgroup which manages the counter correctly:
g, ctx := errgroup.WithContext(ctx)
for _, it := range items { it := it; g.Go(func() error { return process(ctx, it) }) }
return g.Wait()

无效尝试

常见但无效的做法:

  1. 85% 失败

    Race: Wait() may return before the goroutine has called Add, causing Done to decrement below zero or the wait to miss the goroutine.

  2. 80% 失败

    The counter is already corrupted; recover leaves the WaitGroup in an invalid state.