<br><br><div class="gmail_quote"><div dir="ltr">On Mon, Jan 28, 2019, 4:27 PM  <<a href="mailto:paul.robinson@sony.com">paul.robinson@sony.com</a> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">





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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">I have llvm-mc working on empty (or comment-only) source, but not clang yet.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Are you possibly using a Release build? the crashes I see are assertions.</span></p></div></div></blockquote></div><div>I've been running on a full debug build, including assertions. :/</div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div lang="EN-US" link="blue" vlink="purple"><div class="m_-3296255047959154409WordSection1"><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Will keep on it tomorrow.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">--paulr<u></u><u></u></span></p>
<p class="MsoNormal"><a name="m_-3296255047959154409__MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></a></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:<a href="mailto:dblaikie@gmail.com" target="_blank">dblaikie@gmail.com</a>]
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<b>Sent:</b> Monday, January 28, 2019 2:44 PM<br>
<b>To:</b> Robinson, Paul<br>
<b>Cc:</b> <a href="mailto:llvm-commits@lists.llvm.org" target="_blank">llvm-commits@lists.llvm.org</a><br>
<b>Subject:</b> Re: [llvm] r328805 - Reapply "[DWARFv5] Emit file 0 to the line table."<u></u><u></u></span></p>
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<p class="MsoNormal">On Mon, Jan 28, 2019 at 11:12 AM <<a href="mailto:paul.robinson@sony.com" target="_blank">paul.robinson@sony.com</a>> wrote:<u></u><u></u></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Hey Paul,<br>
<br>
I've been experimenting with DWARFv5 broadly applied to some code at Google & found that clang crashes when trying to emit DWARFv5 on an empty assembly file. Turns out llvm-mc does not because of the above code block.<br>
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Seems this support is here for llvm-mc, but missing from clang's initialization of MCContext for cc1as. <br>
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Could you refactor/common/add equivalent functionality to Clang's cc1as? (looks like somewhere near clang/tools/driver/cc1as_main.cpp:400? (since that is where "setMainFileName" is, which is near this block in llvm-mc too))<br>
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- Dave<u></u><u></u></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">You mean, like a zero-length file?  For me, `llvm-mc –g t.s` also crashes with that.  Or a .s file
 with only a comment in it.</span><u></u><u></u></p>
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Hmm, llvm-mc doesn't seem to crash for me... <br>
 <u></u><u></u></p>
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<p class="MsoNormal"><a name="m_-3296255047959154409_m_-3049507084729376003__MailEndCompose"></a><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Looks like clang and llvm-mc crash in different
 places too.</span><u></u><u></u></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<p class="MsoNormal">Maybe different default targets, etc? Not sure.<u></u><u></u></p>
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<p class="MsoNormal"> <u></u><u></u></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> I'll take a look.</span><u></u><u></u></p>
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Thanks!<br>
 <u></u><u></u></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">--paulr</span><u></u><u></u></p>
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