<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">Hi All,<br><br>I&#39;ve been doing lots of tests with CBC 2.8.8 using MIPLIB 2010 instances.<br><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">
It is crashing while solving instance msc98-ip (<br><a href="http://miplib.zib.de/miplib2010/msc98-ip.php">http://miplib.zib.de/miplib2010/msc98-ip.php</a>).<br><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">
There is an assert in <b>CglFlowCover.cpp:1185</b> which is failing apparently because an empty cut is being generated.<br><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">
The relevant part of the stack trace is:<br><br>#3  0x00007fc190e22192 in __GI___assert_fail (assertion=0x7fc1935a1c1e &quot;cutLen&quot;, file=0x7fc1935a1bfe &quot;CglFlowCover.cpp&quot;, line=1185, <br>    function=0x7fc1935a2100 &quot;bool CglFlowCover::generateOneFlowCut(const OsiSolverInterface&amp;, int, int*, double*, char, double, OsiRowCut&amp;, double&amp;)&quot;)<br>
    at assert.c:103<br>#4  0x00007fc1934f475c in CglFlowCover::generateOneFlowCut (this=&lt;optimized out&gt;, si=..., rowLen=&lt;optimized out&gt;, ind=&lt;optimized out&gt;, coef=0xbc6d080, <br>    sense=&lt;optimized out&gt;, rhs=48, flowCut=..., violation=@0x7fff058a6a60: 0.45575080610249774) at CglFlowCover.cpp:1185<br>
#5  0x00007fc1934f4b76 in CglFlowCover::generateCuts (this=0x1d291be0, si=..., cs=..., info=...) at CglFlowCover.cpp:320<br>#6  0x00007fc193c45625 in CbcCutGenerator::generateCuts (this=0x12e92580, cs=..., fullScan=&lt;optimized out&gt;, solver=0x10aa67d8, node=0x0)<br>
    at CbcCutGenerator.cpp:306<br>#7  0x00007fc193c94518 in CbcModel::serialCuts (this=0x2611e10, theseCuts=..., node=0x0, slackCuts=..., lastNumberCuts=368) at CbcModel.cpp:9313<br>#8  0x00007fc193c96e3a in CbcModel::solveWithCuts (this=0x2611e10, cuts=..., numberTries=15, node=0x0) at CbcModel.cpp:7954<br>
#9  0x00007fc193c9f9c9 in CbcModel::branchAndBound (this=&lt;optimized out&gt;, doStatistics=0) at CbcModel.cpp:2905<br>#10 0x00007fc193f82c06 in CbcMain1 (argc=10, argv=0x7fff058b1198, model=..., callBack=0x7fc193f6c1a0 &lt;dummyCallBack(CbcModel*, int)&gt;)<br>
    at CbcSolver.cpp:6171<br>#11 0x0000000000400be3 in main (argc=10, argv=0x7fff058b1198) at CoinSolve.cpp:336<br><br><br></div><br>-- <br><span style="font-family:courier new,monospace">=============================================================<br>
Haroldo Gambini Santos<br>Computing Department<br>Universidade Federal de Ouro Preto - UFOP<br>email: haroldo [at ] <a href="http://iceb.ufop.br" target="_blank">iceb.ufop.br</a><br>home/research page: <a href="http://www.decom.ufop.br/haroldo/" target="_blank">www.decom.ufop.br/haroldo</a><br>
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