</pre>

<h3 id="Package_clause">Package clause</h3>

<p>
A package clause begins each source file and defines the package
to which the file belongs.
</p>

<pre class="ebnf">
PackageClause  = "package" PackageName .
PackageName    = identifier .
</pre>

<p>
The PackageName must not be the <a href="#Blank_identifier">blank identifier</a>.
</p>

<pre>
package math
</pre>

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>

<p class="rule">
The completion of all <code>init</code> functions is synchronized before

  approximately 1% by deduplicating redundant metadata.
  Some programs may see a smaller improvement because this change adjusts the size
  class boundaries of the memory allocator, so some objects may be moved up a size
  class.
</p>
<p>
  A consequence of this change is that some objects' addresses that were previously
  always aligned to a 16 byte (or higher) boundary will now only be aligned to an 8

</pre>

<h3 id="Package_clause">Package clause</h3>

<p>
A package clause begins each source file and defines the package
to which the file belongs.
</p>

<pre class="ebnf">
PackageClause  = "package" PackageName .
PackageName    = identifier .
</pre>

<p>
The PackageName must not be the <a href="#Blank_identifier">blank identifier</a>.
</p>

<pre>
package math
</pre>