go runtime_error ai_generated true

fatal error: all goroutines are asleep - deadlock! (sync.Once.Do calling itself)

ID: go/sync-once-deadlock-recursive

Also available as: JSON · Markdown · 中文
80%Fix Rate
86%Confidence
0Evidence
2024-06-30First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
1.21 active — — —
1.22 active — — —

Root Cause

A sync.Once.Do function calls the same Once.Do again (directly or indirectly), blocking on its own mutex forever.

generic

中文

sync.Once.Do 的函数再次（直接或间接）调用同一个 Once.Do，永久阻塞在自己的互斥锁上。

Workarounds

  1. 95% success 
    Ensure the function passed to Do never calls the same Once; extract shared init into a separate helper
  2. 88% success 
    Use sync.OnceFunc/OnceValue (Go 1.21+) and keep init logic non-reentrant

Dead Ends

Common approaches that don't work:

  1. 90% fail

    Once holds an internal mutex with no timeout support; deadlock persists

  2. 80% fail

    Loses thread-safety; introduces data races