sync: WaitGroup.Go: document that f must not panic

Fixes #63796

Change-Id: Ib11d32574011e13aab3a0ad504f0d10009627503
Reviewed-on: https://go-review.googlesource.com/c/go/+/667695
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>
Commit-Queue: Alan Donovan <adonovan@google.com>
Auto-Submit: Alan Donovan <adonovan@google.com>

diff --git a/src/sync/waitgroup.go b/src/sync/waitgroup.go
index 811857bb231cc2b1b86507d5d551be428a61830e..c850f58ed14e41817f5911b2d35b23f6a9127602 100644 (file)
--- a/src/sync/waitgroup.go
+++ b/src/sync/waitgroup.go
@@ -163,6 +163,8 @@ func (wg *WaitGroup) Wait() {
 // Go calls f in a new goroutine and adds that task to the [WaitGroup].
 // When f returns, the task is removed from the WaitGroup.
 //
+// The function f must not panic.
+//
 // If the WaitGroup is empty, Go must happen before a [WaitGroup.Wait].
 // Typically, this simply means Go is called to start tasks before Wait is called.
 // If the WaitGroup is not empty, Go may happen at any time.