From: jgrosseo <jgrosseo@cern.ch>
Date: Tue, 13 Jan 2015 13:34:10 +0000 (+0100)
Subject: protection against xPDFmotherOld == 0
X-Git-Url: http://git.uio.no/git/?a=commitdiff_plain;h=0f8608128236db8d26d5668fbf579626eb9b7deb;p=u%2Fmrichter%2FAliRoot.git

protection against xPDFmotherOld == 0
---

diff --git a/PYTHIA8/pythia8175/src/SpaceShower.cxx b/PYTHIA8/pythia8175/src/SpaceShower.cxx
index 00005a7154c..52707afd6b0 100644
--- a/PYTHIA8/pythia8175/src/SpaceShower.cxx
+++ b/PYTHIA8/pythia8175/src/SpaceShower.cxx
@@ -785,6 +785,11 @@ void SpaceShower::pT2nearQCDthreshold( BeamParticle& beam,
   double logM2Lambda2  = log( m2Massive / Lambda2 );
   double xPDFmotherOld = beam.xfISR(iSysNow, 21, xDaughter, 
     factorMultFac * m2Threshold);
+  if (xPDFmotherOld == 0) {
+    infoPtr->errorMsg("Error in SpaceShower::pT2nearQCDthreshold: "
+      "xPDFmotherOld is 0"); 
+    return; 
+  }
 
   // Variables used inside evolution loop. (Mainly dummy start values.)
   int    loop    = 0;