var context.cancelCtxKey

5 uses

	context (current package)
		context.go#L289: var cancelCtxKey int
		context.go#L302: 	p, ok := parent.Value(&cancelCtxKey).(*cancelCtx)
		context.go#L352: 	if key == &cancelCtxKey {
		context.go#L578: 			if key == &cancelCtxKey {
		context.go#L583: 			if key == &cancelCtxKey {