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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">My clang problems turned out to be pilot error. Try r352541 and let me know.<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, January 28, 2019 7:47 PM<br>
<b>To:</b> Robinson, Paul<br>
<b>Cc:</b> llvm-commits@lists.llvm.org<br>
<b>Subject:</b> Re: [llvm] r328805 - Reapply "[DWARFv5] Emit file 0 to the line table."<o:p></o:p></span></p>
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<p class="MsoNormal">On Mon, Jan 28, 2019, 4:27 PM <<a href="mailto:paul.robinson@sony.com">paul.robinson@sony.com</a> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><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.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><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><o:p></o:p></p>
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<p class="MsoNormal">I've been running on a full debug build, including assertions. :/<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Will keep on it tomorrow.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><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>]
<br>
<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."</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:12.0pt"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On Mon, Jan 28, 2019 at 11:12 AM <<a href="mailto:paul.robinson@sony.com" target="_blank">paul.robinson@sony.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;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>
<br>
Seems this support is here for llvm-mc, but missing from clang's initialization of MCContext for cc1as. <br>
<br>
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>
<br>
- Dave<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><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><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><br>
Hmm, llvm-mc doesn't seem to crash for me... <br>
<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><a name="m_-3296255047959154409_m_-30495070847293"></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><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Maybe different default targets, etc? Not sure.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> I'll take a look.</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><br>
Thanks!<br>
<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr</span><o:p></o:p></p>
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