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<h5 class="subsubsection">15.4.9.9 <span class="sc">gdb</span> and Modula-2</h5>

<p>Some <span class="sc">gdb</span> 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><span class="samp">vtbl</span></samp>&rsquo;, &lsquo;<samp><span class="samp">demangle</span></samp>&rsquo;,
&lsquo;<samp><span class="samp">asm-demangle</span></samp>&rsquo;, &lsquo;<samp><span class="samp">object</span></samp>&rsquo;, and &lsquo;<samp><span class="samp">union</span></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>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 <dfn>dynamic arrays</dfn>, 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><span class="samp">{</span><var>type</var><span class="samp">}</span><var>adrexp</var></samp>&rsquo; is still useful.

   <p><a name="index-g_t_0040code_007b_0023_007d-in-Modula_002d2-1055"></a>In <span class="sc">gdb</span> scripts, the Modula-2 inequality operator <code>#</code> is
interpreted as the beginning of a comment.  Use <code>&lt;&gt;</code> instead.

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