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| <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 ‘<samp><span class="samp">b</span></samp>’ symbol descriptor. |
| |
| <p>For example, the Fortran declarations |
| |
| <pre class="example"> real foo, foo10(10), foo10_5(10,5) |
| pointer (foop, foo) |
| pointer (foo10p, foo10) |
| pointer (foo105p, foo10_5) |
| </pre> |
| <p>produce the stabs |
| |
| <pre class="example"> foo:b6 |
| foo10:bar3;1;10;6 |
| foo10_5:bar3;1;5;ar3;1;10;6 |
| </pre> |
| <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>The ‘<samp><span class="samp">b</span></samp>’ symbol descriptor is like ‘<samp><span class="samp">V</span></samp>’ 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. |
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