In all these examples, the solution is the same:
use explicit synchronization.
</p>

<h2 id="badcompiler">Incorrect compilation</h2>

<p>
The Go memory model restricts compiler optimizations as much as it does Go programs.
Some compiler optimizations that would be valid in single-threaded programs are not valid in all Go programs.
In particular, a compiler must not introduce writes that do not exist in the original program,

<li>The global generator accessed by top-level functions is unconditionally randomly seeded.
Because the API guarantees no fixed sequence of results,
optimizations like per-thread random generator states are now possible.

<li>The <a href="/pkg/math/rand/v2/#Source"><code>Source</code></a>
interface now has a single <code>Uint64</code> method;