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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Intuitively I'd think MC and DebugInfo should be independent. MC is a producer, DebugInfo is a consumer. What's common is the definition of the structures
they operate on, which doesn't properly belong to either one.<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>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></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""> llvm-dev [mailto:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>David Blaikie via llvm-dev<br>
<b>Sent:</b> Wednesday, March 21, 2018 11:52 AM<br>
<b>To:</b> Zachary Turner<br>
<b>Cc:</b> llvm-dev<br>
<b>Subject:</b> Re: [llvm-dev] CodeView layering<o:p></o:p></span></p>
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<p class="MsoNormal">Someone internally's been dabbling with turning on some of Google's build system's stricter header checking modes - and they caught these (you can check the internal code review 184305506 for the original where I'm pulling things out from).<br>
<br>
& yeah, fair question about the modules builds - I don't fully understand what they catch and don't catch. I suspect it's a matter of whether the headers themselves form a cycle - whereas the Google build system's a bit more structured - knowing about libraries
and explicit dependencies between them.<br>
<br>
& I didn't look closely to see if, as I said, MC could depend on DebugInfoCodeView - probably weird/awkward/not what we want (I'm guessing?) but the modules buildbots don't have explicit dependencies, they just fail when they find a cycle. So they can implicitly
support all sorts of weird dependencies we might not've expected/planned, so long as it's not an actual cycle (& only within the headers - so the modules system might be like "oh, sure, MC can depend on DebugInfoCodeView" but the library dependency might be
the exact opposite (some MC .cpp file could call into DebugInfoCodeView & the modules build wouldn't fail - it knows nothing about .cpp modularity/grouping, just headers))<o:p></o:p></p>
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<p class="MsoNormal">On Wed, Mar 21, 2018 at 11:42 AM Zachary Turner <<a href="mailto:zturner@google.com">zturner@google.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Yes, some of the headers and stuff that are just raw structure definitions and enums could probably be sunk into BinaryFormat..<o:p></o:p></p>
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<p class="MsoNormal">How'd you find this? Curious why it hasn't been breaking in modules builds for a long time.<o:p></o:p></p>
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<p class="MsoNormal">On Wed, Mar 21, 2018 at 11:31 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" style="margin-bottom:12.0pt">I'm looking at fixing some layering violations in LLVM & came across a few in the CodeView handling, specifically:<br>
<br>
lib/MC/MCCodeView includes several llvm/DebugInfo/CodeView headers<br>
I guess MC could be made dependent on DebugInfoCodeView? But probably these things should be sunk into BinaryFormat as is the case for DWARF features used by MC?<o:p></o:p></p>
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<p class="MsoNormal">include/llvm/Object/COFF.h includes include/llvm/DebugInfo/CodeView/CVDebugRecord.h<br>
Also seems like this could/should/needs to be sunk into BinaryFormat?<br>
<br>
I'm open to ideas & happy to do the work, or help in any way that might be useful.<br>
<br>
Thanks,<br>
- Dave<o:p></o:p></p>
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