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Hi,<br>
<br>
No, it shouldn't reason or warn about strict aliasing. It
potentially could and i'd love it to, but as of now it doesn't. When
it does, like in <a class="moz-txt-link-freetext" href="https://bugs.llvm.org/show_bug.cgi?id=47727">https://bugs.llvm.org/show_bug.cgi?id=47727</a>, it's a
bug in the static analyzer, namely yet another instance of
<a class="moz-txt-link-freetext" href="https://bugs.llvm.org/show_bug.cgi?id=44114">https://bugs.llvm.org/show_bug.cgi?id=44114</a>. In particular, if you
change one of the types to char (or something like that), it'll
bypass the strict aliasing rule and the analyzer would still emit a
warning which would then be a definite false positive. I'll reply to
that bug report.<br>
<br>
<div class="moz-cite-prefix">On 10/28/20 2:31 AM, Sam Elliott via
cfe-dev wrote:<br>
</div>
<blockquote type="cite"
cite="mid:B02ECE1F-714C-4B68-A34E-550C22F19F1B@lowrisc.org">
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Hi Cfe-dev,
<div class=""><br class="">
</div>
<div class="">I'm not particularly familiar with the clang static
analzyer, so would like some help with a bug that was filed
against it (when compiling for RISC-V, but I don't think that's
the issue here, as the bug also shows up with the default
target).</div>
<div class=""><br class="">
</div>
<div class="">The bug is here: <a
href="https://bugs.llvm.org/show_bug.cgi?id=47727" class=""
moz-do-not-send="true">https://bugs.llvm.org/show_bug.cgi?id=47727</a></div>
<div class=""><br class="">
</div>
<div class="">Is it expected that the static analzyer will catch
(some?) strict aliasing issues like this?</div>
<div class=""><br class="">
</div>
<div class="">Sam</div>
<div class=""><br class="">
<div class="">
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<div>--</div>
<div>Sam Elliott</div>
<div>Software Team Lead</div>
<div>Senior Software Developer - LLVM
and OpenTitan</div>
<div>lowRISC CIC</div>
</div>
</div>
</div>
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<pre class="moz-quote-pre" wrap="">_______________________________________________
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