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6 <title>Preprocessing and Precompiling</title> |
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10 <h3>Preprocessing and Precompiling</h3> |
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11 <p> When precompiling a header file, the compiler preprocesses the file too. In other words, a precompiled file is preprocessed in the context of its precompilation, not in the context of its compilation. </p> |
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12 <p>The preprocessor also tracks macros used to guard <span class="code">#include</span> files to reduce parsing time. Thus, if a file’s contents are surrounded with:</p> |
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13 <p class="listing">#ifndef FOO_H<br /> |
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16 #endif</p> |
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17 <p>The compiler will not load the file twice, saving some small amount of time in the process.</p> |
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18 <div id="footer">Copyright © 2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. <br>License: <a href="http://www.eclipse.org/legal/epl-v10.html">http://www.eclipse.org/legal/epl-v10.html</a></div> |
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