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| <a name="Compound-Lvalues-1"></a> |
| <h4 class="subsection">11.5.2 Compound Lvalues</h4> |
| <a name="index-Compound-Lvalues"></a> |
| |
| <p>Currently compound lvalues involving array and structure field references |
| are not broken down; an expression like <code>a.b[2] = 42</code> is not reduced |
| any further (though complex array subscripts are). This restriction is a |
| workaround for limitations in later optimizers; if we were to convert this |
| to |
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| <div class="smallexample"> |
| <pre class="smallexample">T1 = &a.b; |
| T1[2] = 42; |
| </pre></div> |
| |
| <p>alias analysis would not remember that the reference to <code>T1[2]</code> came |
| by way of <code>a.b</code>, so it would think that the assignment could alias |
| another member of <code>a</code>; this broke <code>struct-alias-1.c</code>. Future |
| optimizer improvements may make this limitation unnecessary. |
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