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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><atomic> should work both in win32 and pthread versions of MinGW. <mutex> and <thread> are only supported in the pthread version though.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Johannes S. Mueller-Roemer, MSc<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Wiss. Mitarbeiter - Interactive Engineering Technologies (IET)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Fraunhofer-Institut für Graphische Datenverarbeitung IGD<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Fraunhoferstr. 5 | 64283 Darmstadt | Germany<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Tel +49 6151 155-606 | Fax +49 6151 155-139<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">johannes.mueller-roemer@igd.fraunhofer.de | www.igd.fraunhofer.de<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Yaron Keren [mailto:yaron.keren@gmail.com]
<br>
<b>Sent:</b> Wednesday, September 24, 2014 11:56<br>
<b>To:</b> Mueller-Roemer, Johannes Sebastian<br>
<b>Cc:</b> Chandler Carruth; LLVM Developers Mailing List; clang-dev Developers; lldb-dev@cs.uiuc.edu; Chris Bieneman; Reid Kleckner; David Majnemer; Alex Rosenberg; Zachary Turner<br>
<b>Subject:</b> Re: [LLVMdev] RFC: LLVM should require a working C++11 <thread>, <mutex>, and <atomic><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Indeed, mingw and pthreads have C++11 atomics, so building clang (with atomics) should be possible even in cross compilation. I have no idea what is the win from *not* using winpthreads, it is one small DLL file with BSD license.<o:p></o:p></p>
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<p class="MsoNormal">For context (does not matter to mingw as host for buiilding clang but matters for clang running with mingw environment), clang TLS implementation is not same as mingw so atomics do not work for clang+mingw pthreads unless you replace libstdc++
with libcxx compiled by clang. Even there may be troubles with mingw-compiled libraries.<o:p></o:p></p>
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<p class="MsoNormal">libc++ could be built with mingw-w64. I had worked for a while with mingw-w64 distribution with the C++ includes and libstdc++ replaced by the libcxx files and dll respectively. It mostly works but there were many issues in tests. I'm not
sure what is the value of this configuration unless it is start of road to independent clang-based 'gnu flavor' windows toolchain.<o:p></o:p></p>
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<p class="MsoNormal">2014-09-24 9:06 GMT+03:00 Mueller-Roemer, Johannes Sebastian <<a href="mailto:Johannes.Sebastian.Mueller-Roemer@igd.fraunhofer.de" target="_blank">Johannes.Sebastian.Mueller-Roemer@igd.fraunhofer.de</a>>:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I would love to see libc++ working on Windows. In any case, I personally use MinGW with
pthreads, as that supports std::thread etc. Yes, it uses libwinpthread, but that shouldn’t really be an issue.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </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">--</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">Johannes S. Mueller-Roemer, MSc</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">Wiss. Mitarbeiter - Interactive Engineering Technologies (IET)</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"> </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">Fraunhofer-Institut für Graphische Datenverarbeitung IGD</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">Fraunhoferstr. 5 | 64283 Darmstadt | Germany</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">Tel +49 6151 155-606 | Fax +49 6151 155-139</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"><a href="mailto:johannes.mueller-roemer@igd.fraunhofer.de" target="_blank">johannes.mueller-roemer@igd.fraunhofer.de</a>
| <a href="http://www.igd.fraunhofer.de" target="_blank">www.igd.fraunhofer.de</a></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"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">
<a href="mailto:llvmdev-bounces@cs.uiuc.edu" target="_blank">llvmdev-bounces@cs.uiuc.edu</a> [mailto:<a href="mailto:llvmdev-bounces@cs.uiuc.edu" target="_blank">llvmdev-bounces@cs.uiuc.edu</a>]
<b>On Behalf Of </b>Chandler Carruth<br>
<b>Sent:</b> Wednesday, September 24, 2014 03:02<br>
<b>To:</b> LLVM Developers Mailing List; clang-dev Developers; <a href="mailto:lldb-dev@cs.uiuc.edu" target="_blank">
lldb-dev@cs.uiuc.edu</a>; Chris Bieneman; Reid Kleckner; David Majnemer; Alex Rosenberg; Zachary Turner<br>
<b>Subject:</b> [LLVMdev] RFC: LLVM should require a working C++11 <thread>, <mutex>, and <atomic></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">AKA: MinGW + win32threads is holding LLVM (and all of its subprojects) back. We need to stop supporting this host platform.<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">I'm aware of essentially 2 reasonably important use cases for supporting MinGW + win32threads:<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">1) Sane host toolchain on Windows that doesn't require downloading MSVC. (I'm dubious about the value of this one...)<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">2) Cross-compiling a Windows clang.exe (and other tools) from a Linux (or other host) box.<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">Are there others? (And thanks to Reid for explaining these to me!)<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"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I'm somewhat dubious about #1, but if we address #2 it will address any concerns with #1 anyways.<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">I would like to propose that we finish implementing libc++ sufficiently to host Clang on Windows using native Windows APIs to implement things. Then we document very clearly what
is required to download the basic Windows SDK and cross compile Clang (and any other tools) for Windows using just libc++ and the SDK. No need for MSVC bits, etc. Would this be acceptable?<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">If not, would it be acceptable to use libc++ on top of mingw (so just avoiding libstdc++)? I *really* don't want to spend lots of time going there because it seems like a low-value
platform, but we can.<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">Anyways, I want to tease out anything else required here because if this is all we need, I think we can make it a reality and get to a much saner platform.<o:p></o:p></p>
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_______________________________________________<br>
LLVM Developers mailing list<br>
<a href="mailto:LLVMdev@cs.uiuc.edu">LLVMdev@cs.uiuc.edu</a> <a href="http://llvm.cs.uiuc.edu" target="_blank">http://llvm.cs.uiuc.edu</a><br>
<a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" target="_blank">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><o:p></o:p></p>
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