LossyFunctionResultCast.qhelp

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<qhelp>

<overview>
<p>This rule finds function calls whose result type is a floating point type, which are implicitly cast to an integral type. Such code may not behave as intended when the floating point return value has a fractional part, or takes an extreme value outside the range that can be represented by the integer type.</p>

</overview>
<recommendation>
<p>Consider changing the surrounding expression to match the floating point type. If rounding is intended, explicitly round using a standard function such as <code>trunc</code>, <code>floor</code> or <code>round</code>.</p>

</recommendation>
<example><sample src="LossyFunctionResultCast.cpp" />
<p>In this example, the result of the call to <code>getWidth()</code> is implicitly cast to <code>int</code>, resulting in an unintended loss of accuracy. To fix this, the type of variable <code>width</code> could be changed from <code>int</code> to <code>double</code>.</p>

</example>
<references>

<li>
  Microsoft Visual C++ Documentation: <a href="https://docs.microsoft.com/en-us/cpp/cpp/type-conversions-and-type-safety-modern-cpp?view=vs-2017">Type Conversions and Type Safety (Modern C++)</a>.
</li>
<li>
  Cplusplus.com: <a href="http://www.cplusplus.com/doc/tutorial/typecasting/">Type conversions</a>.
</li>

</references>
</qhelp>