assigning to or evaluating <code>x.f</code>
causes a <a href="#Run_time_panics">run-time panic</a>.
</li>

<li>
If <code>x</code> is of interface type and has the value
<code>nil</code>, <a href="#Calls">calling</a> or
<a href="#Method_values">evaluating</a> the method <code>x.f</code>
causes a <a href="#Run_time_panics">run-time panic</a>.
</li>
</ol>

<p>

</p>

<h2 id="synchronization">Synchronization</h2>

<h3 id="init">Initialization</h3>

<p>
Program initialization runs in a single goroutine,
but that goroutine may create other goroutines,
which run concurrently.
</p>

<p class="rule">
If a package <code>p</code> imports package <code>q</code>, the completion of
<code>q</code>'s <code>init</code> functions happens before the start of any of <code>p</code>'s.
</p>

a struct with a <code>_size</code> field), <code>#include
"go_asm.h"</code> will fail with a "redefinition of macro" error.
</p>

<h3 id="runtime">Runtime Coordination</h3>

<p>
For garbage collection to run correctly, the runtime must know the
location of pointers in all global data and in most stack frames.
The Go compiler emits this information when compiling Go source files,
but assembly programs must define it explicitly.
</p>

assigning to or evaluating <code>x.f</code>
causes a <a href="#Run_time_panics">run-time panic</a>.
</li>

<li>
If <code>x</code> is of interface type and has the value
<code>nil</code>, <a href="#Calls">calling</a> or
<a href="#Method_values">evaluating</a> the method <code>x.f</code>
causes a <a href="#Run_time_panics">run-time panic</a>.
</li>
</ol>

<p>