fix

modules/graceful/manager_unix.go

@@ -59,7 +59,15 @@ func (g *Manager) start() {
  go func() {
  defer close(startupDone)
  // Wait till we're done getting all the listeners and then close the unused ones
- g.createServerWaitGroup.Wait()
+ func() {
+ // FIXME: there is a fundamental design problem of the "manager" and the "wait group".
+ // If nothing has started, the "Wait" just panics: sync: WaitGroup is reused before previous Wait has returned
+ // There is no clear solution besides a complete rewriting of the "manager"
+ defer func() {
+ recover()
+ }()
+ g.createServerWaitGroup.Wait()
+ }()
  // Ignore the error here there's not much we can do with it, they're logged in the CloseProvidedListeners function
  _ = CloseProvidedListeners()
  g.notify(readyMsg)

modules/graceful/manager_windows.go

@@ -150,7 +150,15 @@ func (g *Manager) awaitServer(limit time.Duration) bool {
  c := make(chan struct{})
  go func() {
  defer close(c)
- g.createServerWaitGroup.Wait()
+ func() {
+ // FIXME: there is a fundamental design problem of the "manager" and the "wait group".
+ // If nothing has started, the "Wait" just panics: sync: WaitGroup is reused before previous Wait has returned
+ // There is no clear solution besides a complete rewriting of the "manager"
+ defer func() {
+ recover()
+ }()
+ g.createServerWaitGroup.Wait()
+ }()
  }()
  if limit > 0 {
  select {