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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Forgot to say, please commit for me as I don't have access.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks,<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"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><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""> Michael Spencer [mailto:bigcheesegs@gmail.com]
<br>
<b>Sent:</b> Tuesday, March 12, 2013 3:09 PM<br>
<b>To:</b> Robinson, Paul<br>
<b>Cc:</b> llvm-commits@cs.uiuc.edu commits (llvm-commits@cs.uiuc.edu)<br>
<b>Subject:</b> Re: [PATCH] Windows hang with long filename<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Tue, Mar 12, 2013 at 2:33 PM, Robinson, Paul <<a href="mailto:Paul.Robinson@am.sony.com" target="_blank">Paul.Robinson@am.sony.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">This is basically the Windows version of r176226; it avoids a<br>
hang when certain issues arise with an output filename.<br>
We found this because Clang would hang because the output file<br>
pathname exceeded the Windows limit of 260 characters.<br>
Yes, I know the context around the fix is about creating the<br>
parent directory; but that's the loop where the hang occurs.<br>
<br>
Murphy consequence #1: I could not find any LLVM tool that used<br>
unique_file(), only Clang uses this AFAICT. So the test is written<br>
for Clang, which means it has to go in the Clang suite instead of<br>
the LLVM suite.<br>
<br>
Murphy consequence #2: The problem occurs only on Windows, but the<br>
LIT test system apparently has no way to describe a host-specific<br>
test. Linux and others have different limits on output file paths,<br>
so you cannot expect the same behavior across all hosts. I was able<br>
to craft a test that did exercise the problem on Windows without<br>
bumping into different problems on Linux, but the only way I could<br>
get it to be cross-platform is to mark it XFAIL: win32, with a big<br>
comment explaining why.<br>
<br>
I am resigned to the perverseness of the test. I'm willing to have<br>
the test accepted on condition that I file a bug against the test<br>
system for being unable to constrain a test based on the host platform.<br>
I'm also willing to have the test rejected as too stupid to live.<br>
(But don't ask me to implement the \\?\ stuff.)<br>
<br>
Thanks,<br>
--paulr<o:p></o:p></p>
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<p class="MsoNormal">Both patches look good. This would actually still be a problem with \\?\.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">- Michael Spencer<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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