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<a name="Based-Variables"></a>
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<hr>
<a name="Fortran-Based-Variables"></a>
<h3 class="section">4.6 Fortran Based Variables</h3>

<p>Fortran (at least, the Sun and SGI dialects of FORTRAN-77) has a feature
which allows allocating arrays with <code>malloc</code>, but which avoids
blurring the line between arrays and pointers the way that C does.  In
stabs such a variable uses the &lsquo;<samp>b</samp>&rsquo; symbol descriptor.
</p>
<p>For example, the Fortran declarations
</p>
<div class="example">
<pre class="example">real foo, foo10(10), foo10_5(10,5)
pointer (foop, foo)
pointer (foo10p, foo10)
pointer (foo105p, foo10_5)
</pre></div>

<p>produce the stabs
</p>
<div class="example">
<pre class="example">foo:b6
foo10:bar3;1;10;6
foo10_5:bar3;1;5;ar3;1;10;6
</pre></div>

<p>In this example, <code>real</code> is type 6 and type 3 is an integral type
which is the type of the subscripts of the array (probably
<code>integer</code>).
</p>
<p>The &lsquo;<samp>b</samp>&rsquo; symbol descriptor is like &lsquo;<samp>V</samp>&rsquo; in that it denotes a
statically allocated symbol whose scope is local to a function; see
See <a href="Statics.html#Statics">Statics</a>.  The value of the symbol, instead of being the address
of the variable itself, is the address of a pointer to that variable.
So in the above example, the value of the <code>foo</code> stab is the address
of a pointer to a real, the value of the <code>foo10</code> stab is the
address of a pointer to a 10-element array of reals, and the value of
the <code>foo10_5</code> stab is the address of a pointer to a 5-element array
of 10-element arrays of reals.
</p>


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