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<h3>Language-related Strategies</h3>
<p> Language-related strategies limit or avoid the use of ISO C++ features. While these features can make software design and maintenance easier, they can also increase code size.</p>
<ul>
<li>Virtual Functions—Not using virtual functions reduces code size.</li>
<li>Runtime Type Identification—Extra data is not generated if program does not use Runtime Type Identification (RTTI).</li>
<li>Exception Handling—While the Carbide.c++ compiler provides zero-overhead exception handling to provide optimum execution speed, it still generates extra object code for exception support.</li>
<li>Operator New—Do not throw an exception within the new operator.</li>
<li>Multiple and Virtual Inheritance</li>
</ul>
<h4>Virtual Functions</h4>
<p>For optimal code size, do not use virtual functions unless absolutely necessary. A virtual function is never dead-stripped, even if it is never called.</p>
<h4>Runtime Type Identification</h4>
<p>If code size is an issue, do not use RTTI because it generates a data table for every class. Disabling RTTI decreases the size of the data section.</p>
<p>The EC++ proposal does not allow runtime type identification.</p>
<p>See also “Controlling RTTI”.</p>
<h4>Exception Handling</h4>
<p>If you must handle exceptions, be careful when using C++ exception handling routines. Carbide has a zero runtime overhead error handling mechanism. However, using exceptions does increase code size, particularly the exception tables data.</p>
<p>The EC++ proposal does not allow exception handling.</p>
<p class="note"><strong>NOTE</strong> The proposed ISO standard libraries and the use of the new operator require exception handling.</p>
<h4>Operator New</h4>
<p>The C++ new operator might throw an exception, depending on how the runtime library implements the new operator. To make the new operator throw exceptions, set __throws_bad_alloc to 1 in the prefix file for your target and rebuild your library. To prevent the new operator from throwing exceptions, set __throws_bad_alloc to 0 in the prefix file for your target and rebuild your library.</p>
<p>See your release notes or Targeting manual for more information.</p>
<h4>Multiple and Virtual Inheritance</h4>
<p>Implementing multiple inheritance requires a modest amount of code and data overhead. The EC++ proposal does not allow multiple inheritance.</p>
<p>For optimal code size, do not use virtual inheritance. Virtual base classes are often complex and add a lot of code to the constructor and destructor functions.</p>
<p>The EC++ proposal does not allow virtual inheritance.</p>
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