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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Visual Studio up to and including VS2013 implements std::chrono::high_resolution_clock in an absolutely unusable manner
 (it is a very low resolution clock…) [1]. Also, division is implemented incorrectly [2]. I have run into both issues in my private developments, so I would avoid them as long as VS2013 is supported by LLVM (I believe it still is?).<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">    [1]:
<a href="https://stackoverflow.com/questions/31643279">https://stackoverflow.com/questions/31643279</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">    [2]:
<a href="https://stackoverflow.com/questions/26372596">https://stackoverflow.com/questions/26372596</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> llvm-dev [mailto:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>Zachary Turner via llvm-dev<br>
<b>Sent:</b> Friday, October 7, 2016 03:11<br>
<b>To:</b> llvm-dev <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> [llvm-dev] Using std::chrono<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi all,<br>
<br>
We're considering using std::chrono more heavily in lldb. However, A quick search of the llvm, clang, and lld codebases shos almost zero usage of chrono. I wanted to see if this was for technical reasons (eg some compiler doesn't support it well) or simply
 because nobody has needed it yet. If it's the former then I'd like to be aware of the issues so we don't fall into any traps.<br>
<br>
If it's the latter, then we're good to go. Would it be worth adding any chrono helper functions to llvm/Support? On the one hand, it seems generally useful. But on the other hand, if nobody's using it yet, maybe it's not generally useful enough.<br>
<br>
Also, are there any chrono experts around who would be willing to review some patches?<o:p></o:p></p>
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