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Uh, my bad!<br>
<br>
I was checking whether such functionality was already implemented by
running analysis on the sample piece of code provided by the checker
description in the list, I didn't see any warning, so I assumed it's
not there.<br>
<br>
Thank you very much for the feedback! I'll pick another item from
the list :)<br>
<br>
Goodbye,<br>
<br>
--<br>
Kirill Bobyrev<br class="">
<a moz-do-not-send="true" href="https://github.com/omtcyf0"
target="_blank" class="">https://github.com/omtcyf0</a><br>
<br>
<div class="moz-cite-prefix">On 9/3/2015 8:39 AM, Anna Zaks wrote:<br>
</div>
<blockquote
cite="mid:E48DCBDF-E676-474E-BBC0-C0623D4DDE16@apple.com"
type="cite">
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<div class="">Hi Kirill,</div>
<div class=""><br class="">
</div>
<div class="">The checkPreStmt callback should be used by checkers
that require symbolic execution. Check out the video of our talk
for introduction into how that works <a moz-do-not-send="true"
href="http://llvm.org/devmtg/2012-11/videos/Zaks-Rose-Checker24Hours.mp4"
class="">http://llvm.org/devmtg/2012-11/videos/Zaks-Rose-Checker24Hours.mp4</a>.
Looks like this checker is only performing a syntactic check, so
using an AST visitor would be more appropriate <a
moz-do-not-send="true"
href="http://clang-analyzer.llvm.org/checker_dev_manual.html#ast"
class=""><a class="moz-txt-link-freetext" href="http://clang-analyzer.llvm.org/checker_dev_manual.html#ast">http://clang-analyzer.llvm.org/checker_dev_manual.html#ast</a></a>.</div>
<div class=""><br class="">
</div>
<div class="">However, most importantly, similar functionality is
already implemented in the compiler (see -Wfloat-equal)! Looks
like it does not work when comparing against a constant. I am
not sure what the reason for that is; was it a a source of false
positives or just an oversight.</div>
<div class=""><br class="">
</div>
<div class="">Since the warning is in place, we should remove this
from the list of checkers to be implemented.</div>
<div class=""><br class="">
</div>
<div class="">Thank you,</div>
<div class="">Anna.</div>
<div class=""><br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Sep 2, 2015, at 2:58 PM, Kirill Bobyrev via
cfe-dev <<a moz-do-not-send="true"
href="mailto:cfe-dev@lists.llvm.org" class="">cfe-dev@lists.llvm.org</a>>
wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div dir="ltr" class="">
<div bgcolor="#FFFFFF" text="#000000" class=""> I've
started implementing different.FloatingCompare checker
from the <a moz-do-not-send="true"
href="http://clang-analyzer.llvm.org/potential_checkers.html"
class="">list of potential checkers</a>. I'd like to
gather some feedback and do some improvements in order
to push the code to the upstream in the near future.</div>
<div bgcolor="#FFFFFF" text="#000000" class=""><br
class="">
</div>
<div bgcolor="#FFFFFF" text="#000000" class="">Vassil
Vassilev mentioned it might be reasonable if the
checker could detect that there is division which
might yield precision loss and then detect a check
against a 'constant' values.</div>
<div bgcolor="#FFFFFF" text="#000000" class=""><br
class="">
</div>
<div bgcolor="#FFFFFF" text="#000000" class="">What do
you think? What should be the checker's default
behavior?</div>
<div bgcolor="#FFFFFF" text="#000000" class=""><br
class="">
</div>
<div bgcolor="#FFFFFF" text="#000000" class="">The first
version of checker is attached.</div>
<div bgcolor="#FFFFFF" text="#000000" class=""> <br
class="">
--<br class="">
Kirill Bobyrev<br class="">
<a moz-do-not-send="true"
href="https://github.com/omtcyf0" target="_blank"
class="">https://github.com/omtcyf0</a><br class="">
</div>
</div>
<span id="cid:2A870EB9-86D3-4EB0-9FA5-635750006BF6"><FloatingCompareChecker.patch></span>_______________________________________________<br
class="">
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<a moz-do-not-send="true"
href="mailto:cfe-dev@lists.llvm.org" class="">cfe-dev@lists.llvm.org</a><br
class="">
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class="">
</div>
</blockquote>
</div>
<br class="">
</div>
</blockquote>
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