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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal> I am observing a deadlock with llvm-lit on windows 7.<o:p></o:p></p><p class=MsoNormal>When I attached a debugger, the communicate() call is blocked.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>In file utils/lit/lit/TestRunner.py<o:p></o:p></p><p class=MsoNormal>> # FIXME: There is probably still deadlock potential here. Yawn.<o:p></o:p></p><p class=MsoNormal>> procData = [None] * len(procs)<o:p></o:p></p><p class=MsoNormal>> procData[-1] = procs[-1].communicate()<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I am invoking python directly on windows to run the unit tests. <o:p></o:p></p><p class=MsoNormal>C:\Python27\python.exe C:\build\llvm\Release\bin\llvm-lit.py -v -j 12 --param build_mode=Release --param build_config=Win32 llvm_site_config=C:\llvm_on_win\nightly\build\llvm\tools\polly\test\lit.site.cfg test<o:p></o:p></p><p class=MsoNormal>Note: If I invoke with “-j 1” , the unit tests finish but took a lot of time. There is no deadlock. I am using python version 2.7.6.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>At this moment, I believe the issue is caused by stdout filling the OS buffer there by blocking the communicate() call.<o:p></o:p></p><p class=MsoNormal>It is possible some of the unit tests dump a lot of text/data to stdout. FYI, I have a couple of unit tests of my own in the code base.<o:p></o:p></p><p class=MsoNormal>On Linux, there is no deadlock but on windows I am hitting a deadlock 7 out of 10 times. I tried invoking python with “-u” but in vain.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>When I looked at llvm-lit code, I saw the code to avoid deadlocks but there was no guarantee, like the one I pasted above.<o:p></o:p></p><p class=MsoNormal>Would appreciate if some one take a look at it and provide more context on deadlocks.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>--Sumanth G<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>