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<h5 class="subsubsection">15.4.1.5 C and C<tt>++</tt> Type and Range Checks</h5>

<p><a name="index-C-and-C_0040t_007b_002b_002b_007d-checks-813"></a>
By default, when <span class="sc">gdb</span> parses C or C<tt>++</tt> expressions, type checking
is not used.  However, if you turn type checking on, <span class="sc">gdb</span>
considers two variables type equivalent if:

     <ul>
<li>The two variables are structured and have the same structure, union, or
enumerated tag.

     <li>The two variables have the same type name, or types that have been
declared equivalent through <code>typedef</code>.

   </ul>

   <p>Range checking, if turned on, is done on mathematical operations.  Array
indices are not checked, since they are often used to index a pointer
that is not itself an array.

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