<p>
The exit of a goroutine is not guaranteed to be synchronized before
any event in the program.
For example, in this program:
</p>

<pre>
var a string

func hello() {
	go func() { a = "hello" }()
	print(a)
}
</pre>

<p>
the assignment to <code>a</code> is not followed by
any synchronization event, so it is not guaranteed to be
observed by any other goroutine.

  more than 8-byte aligned and rely on the memory allocator's previous alignment behavior
  may break, but we expect such programs to be rare.
  Such programs may be built with <code>GOEXPERIMENT=noallocheaders</code> to revert
  to the old metadata layout and restore the previous alignment behavior, but package
  owners should update their assembly code to avoid the alignment assumption, as this
  workaround will be removed in a future release.