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57 lines
2.0 KiB
XML
57 lines
2.0 KiB
XML
<!DOCTYPE qhelp PUBLIC
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"-//Semmle//qhelp//EN"
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"qhelp.dtd">
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<qhelp>
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<overview>
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<p>Use of <code>goto</code> statements makes code more difficult to understand and maintain.
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Consequently, the use of <code>goto</code> statements is deprecated except as a mechanism
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for breaking out of multiple nested loops, or jumping to error-handling code at
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the end of a function. This rule identifies complex (and therefore hard to
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understand) uses of <code>goto</code> statements. Function bodies that include
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multiple <code>goto</code> statements that jump forward and multiple
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<code>goto</code> statements that jump backwards are highlighted.</p>
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</overview>
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<recommendation>
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<p>
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In most cases the code can be rewritten and/or rearranged by:
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</p>
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<ul>
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<li>using structured control flow constructs, such as <code>if</code>, <code>while</code>,
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and <code>for</code>;</li>
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<li>using <code>break</code> or <code>continue</code> to stop a loop iteration early; or</li>
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<li>using <code>return</code> to exit a function early</li>
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</ul>
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<p>
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The <code>goto</code> statement may be the best solution for breaking out of
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deeply nested loops, or for jumping to error handling code, without adversely
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affecting the readability of the function. Such uses will not be flagged by
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this rule.
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</p>
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</recommendation>
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<references>
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<li>
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<em>Joint Strike Fighter Air Vehicle C++ Coding Standards</em>, AV Rule 189. Lockheed Martin Corporation, 2005.
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</li>
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<li>
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E. W. Dijkstra Archive: <a href="http://www.cs.utexas.edu/users/EWD/transcriptions/EWD02xx/EWD215.html">A Case against the GO TO Statement (EWD-215)</a>.
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</li>
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<li>
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MSDN Library: <a href="https://docs.microsoft.com/en-us/cpp/cpp/goto-statement-cpp">goto Statement (C++)</a>.
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</li>
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<li>
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Mats Henricson and Erik Nyquist, <i>Industrial Strength C++</i>, Rule 4.6. Prentice Hall PTR, 1997.
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(<a href="https://web.archive.org/web/20190919025638/https://mongers.org/industrial-c++/">PDF</a>).
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</li>
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<li>
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cplusplus.com: <a href="http://www.cplusplus.com/doc/tutorial/control/">Control Structures</a>.
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</li>
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</references>
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</qhelp>
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