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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Seems reasonable to me.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> David Blaikie [mailto:dblaikie@gmail.com]
<br>
<b>Sent:</b> Monday, December 17, 2018 3:35 AM<br>
<b>To:</b> Adrian Prantl<br>
<b>Cc:</b> llvm-dev; Jonas Devlieghere; Robinson, Paul; Eric Christopher<br>
<b>Subject:</b> Re: DebugInfo proposal: Emit an explicit empty address range on CUs with no code addresses<o:p></o:p></span></p>
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<p class="MsoNormal">Looks like I argued (& then tested) previously for support for the case where the CU has no ranges, but sub-DIEs do: <a href="http://lists.llvm.org/pipermail/llvm-dev/2017-November/119131.html" target="_blank">http://lists.llvm.org/pipermail/llvm-dev/2017-November/119131.html</a><br>
<br>
(Just for the record, LLVM gained support for CU ranges were implemented r<span style="color:#212121">197776, December 2013 (& shortly after that became the default in r</span><span style="font-size:10.0pt;color:#212121">203968, March 2014 - in the 3.</span><span style="color:#212121">5
release) - looks like GCC got this somewhere between GCC 4.1 and GCC 4.4 according to godbolt testing, so on/before March 2012 I think)</span><o:p></o:p></p>
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<br>
So I've gone ahead and committed this change in r349333 - open to further discussion, reverting it, etc.<br>
<br>
- Dave<br>
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<p class="MsoNormal">On Wed, Nov 28, 2018 at 10:48 AM David Blaikie <<a href="mailto:dblaikie@gmail.com" target="_blank">dblaikie@gmail.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Yeah, fair - I'll give it a week or something, see if Paul or anyone else has ideas about why the existing behavior might be useful before I remove it.<o:p></o:p></p>
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<p class="MsoNormal">On Wed, Nov 28, 2018 at 10:27 AM Adrian Prantl <<a href="mailto:aprantl@apple.com" target="_blank">aprantl@apple.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">On Nov 28, 2018, at 9:50 AM, David Blaikie <<a href="mailto:dblaikie@gmail.com" target="_blank">dblaikie@gmail.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Helvetica","sans-serif"">> a) decide that a unit without ranges covers no ranges - and don't do the search<br>
<br>
Are there compilers that do this ("forget" to emit ranges) that we care to support with llvm-symbolizer?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Helvetica","sans-serif""><br>
I'm not specifically aware of any, though haven't gone looking.<o:p></o:p></span></p>
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<p class="MsoNormal">Just in case this wasn't obvious in the sub-text:<o:p></o:p></p>
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<p class="MsoNormal">I think we should figure out whether this assumption in llvm-symbolizer is actually needed to support a compiler we care about and then potentially remove it, or enforce it only when the CU is < DWARF 5 or something like that.<o:p></o:p></p>
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<p class="MsoNormal">-- adrian<o:p></o:p></p>
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