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15<title>STABS: Based Variables</title>
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62<a name="Based-Variables"></a>
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64<p>
65Next: <a href="Parameters.html#Parameters" accesskey="n" rel="next">Parameters</a>, Previous: <a href="Statics.html#Statics" accesskey="p" rel="previous">Statics</a>, Up: <a href="Variables.html#Variables" accesskey="u" rel="up">Variables</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p>
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68<a name="Fortran-Based-Variables"></a>
69<h3 class="section">4.6 Fortran Based Variables</h3>
70
71<p>Fortran (at least, the Sun and SGI dialects of FORTRAN-77) has a feature
72which allows allocating arrays with <code>malloc</code>, but which avoids
73blurring the line between arrays and pointers the way that C does.  In
74stabs such a variable uses the &lsquo;<samp>b</samp>&rsquo; symbol descriptor.
75</p>
76<p>For example, the Fortran declarations
77</p>
78<div class="example">
79<pre class="example">real foo, foo10(10), foo10_5(10,5)
80pointer (foop, foo)
81pointer (foo10p, foo10)
82pointer (foo105p, foo10_5)
83</pre></div>
84
85<p>produce the stabs
86</p>
87<div class="example">
88<pre class="example">foo:b6
89foo10:bar3;1;10;6
90foo10_5:bar3;1;5;ar3;1;10;6
91</pre></div>
92
93<p>In this example, <code>real</code> is type 6 and type 3 is an integral type
94which is the type of the subscripts of the array (probably
95<code>integer</code>).
96</p>
97<p>The &lsquo;<samp>b</samp>&rsquo; symbol descriptor is like &lsquo;<samp>V</samp>&rsquo; in that it denotes a
98statically allocated symbol whose scope is local to a function; see
99See <a href="Statics.html#Statics">Statics</a>.  The value of the symbol, instead of being the address
100of the variable itself, is the address of a pointer to that variable.
101So in the above example, the value of the <code>foo</code> stab is the address
102of a pointer to a real, the value of the <code>foo10</code> stab is the
103address of a pointer to a 10-element array of reals, and the value of
104the <code>foo10_5</code> stab is the address of a pointer to a 5-element array
105of 10-element arrays of reals.
106</p>
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