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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222;background:white">In the file \lib\Support\Process.cpp on line 60, it seems as though an unnecessary heap allocation and memory leak occurs.</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">This is the offending code:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p> </o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">static TimeValue getElapsedWallTime() {</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"> static TimeValue &StartTime = *new TimeValue(TimeValue::now());</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"> return TimeValue::now() - StartTime;</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">}</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">The issue is that the <i>StartTime</i> variable's value is allocated on the heap, after which a *<b>reference</b>* to it is stored (not the pointer itself). This
means that the allocated memory is actually never properly de-allocated. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">Granted, the memory leak is small but if anyone attempts to write memory leak-free software while including LLVM code, this will be an issue (as it currently
is for our company).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">Is there anyone who knows why exactly this was implemented the way it currently is implemented? It seems rather unnecessary to be implemented with this complexity
when a simpler implementation would work as well:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p> </o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">static TimeValue getElapsedWallTime() {</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"> static TimeValue TimeValue(TimeValue::now());</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"> return TimeValue::now() - StartTime;</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222">}</span></i><span style="font-size:12.0pt;font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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