Which strategy prevents goroutine leaks when using select with buffered channels?

In Go, the select statement is frequently used to handle asynchronous communication across multiple channels. When implementing a pattern where a producer sends data to a buffered channel, there is a risk of goroutine leakage if the consumer stops listening before the producer finishes.

If a producer uses a select block with a default case to avoid blocking, it may drop messages. However, if it blocks on a send operation to a full buffer and the receiver has exited, the producer goroutine remains in memory indefinitely.

What is the most reliable way to ensure a producer goroutine terminates when the receiver is no longer active, without relying on a shared state variable or risking a panic from sending to a closed channel?