*p /= 2
*p += i
</pre>

<p>
If <code>i</code> and <code>*p</code> start equal to 2,
the original code does <code>*p = 3</code>,
so a racing thread can read only 2 or 3 from <code>*p</code>.
The rewritten code does <code>*p = 1</code> and then <code>*p = 3</code>,
allowing a racing thread to read 1 as well.
</p>

<p>
Note that all these optimizations are permitted in C/C++ compilers:

line := Line{origin, Point3D{y: -4, z: 12.3}}  // zero value for line.q.x
</pre>

<p>
For array and slice literals the following rules apply:
</p>
<ul>
	<li>Each element has an associated integer index marking
	    its position in the array.
	</li>
	<li>An element with a key uses the key as its index. The
	    key must be a non-negative constant
	    <a href="#Representability">representable</a> by

line := Line{origin, Point3D{y: -4, z: 12.3}}  // zero value for line.q.x
</pre>

<p>
For array and slice literals the following rules apply:
</p>
<ul>
	<li>Each element has an associated integer index marking
	    its position in the array.
	</li>
	<li>An element with a key uses the key as its index. The
	    key must be a non-negative constant
	    <a href="#Representability">representable</a> by