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<title>Debugging with GDB: GDB/M2</title>

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<a name="GDB-and-Modula_002d2"></a>
<h4 class="subsubsection">15.4.8.9 <small>GDB</small> and Modula-2</h4>

<p>Some <small>GDB</small> commands have little use when debugging Modula-2 programs.
Five subcommands of <code>set print</code> and <code>show print</code> apply
specifically to C and C<tt>++</tt>: &lsquo;<samp>vtbl</samp>&rsquo;, &lsquo;<samp>demangle</samp>&rsquo;,
&lsquo;<samp>asm-demangle</samp>&rsquo;, &lsquo;<samp>object</samp>&rsquo;, and &lsquo;<samp>union</samp>&rsquo;.  The first four
apply to C<tt>++</tt>, and the last to the C <code>union</code> type, which has no direct
analogue in Modula-2.
</p>
<p>The <code>@</code> operator (see <a href="Expressions.html#Expressions">Expressions</a>), while available
with any language, is not useful with Modula-2.  Its
intent is to aid the debugging of <em>dynamic arrays</em>, which cannot be
created in Modula-2 as they can in C or C<tt>++</tt>.  However, because an
address can be specified by an integral constant, the construct
&lsquo;<samp>{<var>type</var>}<var>adrexp</var></samp>&rsquo; is still useful.
</p>
<a name="index-_0023-in-Modula_002d2"></a>
<p>In <small>GDB</small> scripts, the Modula-2 inequality operator <code>#</code> is
interpreted as the beginning of a comment.  Use <code>&lt;&gt;</code> instead.
</p>


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