Program: 91879
Project: 91879
Buggy source:
@Override public void run(){
  for (int i=0; i < tl.size(); i++) {
    TmfTraceElement traceel=tl.get(i);
    ITmfTrace expTrace=null;
    for (    ITmfTrace t : experiment.getTraces()) {
      if (t.getResource().equals(traceel.getResource())) {
        expTrace=t;
        break;
      }
    }
    try {
      if ((expTrace != null) && syncAlgo.isTraceSynced(expTrace.getHostId())) {
        TmfTraceElement origtrace=traceel.getElementUnderTraceFolder();
        if (origtrace != null) {
          String newname=traceel.getName();
          IContainer parentFolder=origtrace.getResource().getParent();
          boolean traceexists;
          do {
            traceexists=false;
            newname+="String_Node_Str";
            if (parentFolder.findMember(newname) != null) {
              traceexists=true;
            }
          }
 while (traceexists);
          TmfTraceElement newtrace=origtrace.copy(newname);
          if (newtrace != null) {
            ITmfTrace trace=newtrace.instantiateTrace();
            ITmfEvent traceEvent=newtrace.instantiateEvent();
            trace.initTrace(newtrace.getResource(),newtrace.getLocation().getPath(),traceEvent.getClass());
            trace.setTimestampTransform(syncAlgo.getTimestampTransform(trace));
            exp.addTrace(newtrace);
            exp.removeTrace(traceel);
          }
 else {
            TraceUtils.displayErrorMsg(Messages.SynchronizeTracesHandler_Title,Messages.SynchronizeTracesHandler_Error + CR + CR+ String.format(Messages.SynchronizeTracesHandler_CopyProblem,origtrace.getName()));
          }
        }
      }
    }
 catch (    CoreException e) {
      Activator.getDefault().logError(String.format(Messages.SynchronizeTracesHandler_ErrorSynchingForTrace,exp.getName(),traceel.getName()),e);
      TraceUtils.displayErrorMsg(Messages.SynchronizeTracesHandler_Title,Messages.SynchronizeTracesHandler_Error + CR + CR+ e.getMessage());
    }
catch (    TmfTraceException e) {
      Activator.getDefault().logError(String.format(Messages.SynchronizeTracesHandler_ErrorSynchingForTrace,exp.getName(),traceel.getName()),e);
      TraceUtils.displayErrorMsg(Messages.SynchronizeTracesHandler_Title,Messages.SynchronizeTracesHandler_Error + CR + CR+ e.getMessage());
    }
  }
}

Fixed version (ground truth):
@Override public void run(){
  List<TmfTraceElement> tracesToAdd=new ArrayList<>();
  List<TmfTraceElement> tracesToRemove=new ArrayList<>();
  for (  TmfTraceElement traceel : tl) {
    ITmfTrace expTrace=null;
    for (    ITmfTrace t : experiment.getTraces()) {
      if (t.getResource().equals(traceel.getResource())) {
        expTrace=t;
        break;
      }
    }
    if ((expTrace != null) && syncAlgo.isTraceSynced(expTrace.getHostId())) {
      TmfTraceElement origtrace=traceel.getElementUnderTraceFolder();
      String newname=traceel.getName();
      IContainer parentFolder=origtrace.getResource().getParent();
      boolean traceexists;
      do {
        traceexists=false;
        newname+="String_Node_Str";
        if (parentFolder.findMember(newname) != null) {
          traceexists=true;
        }
      }
 while (traceexists);
      TmfTraceElement newtrace=origtrace.copy(newname);
      if (newtrace == null) {
        TraceUtils.displayErrorMsg(Messages.SynchronizeTracesHandler_Title,Messages.SynchronizeTracesHandler_Error + CR + CR+ String.format(Messages.SynchronizeTracesHandler_CopyProblem,origtrace.getName()));
        continue;
      }
      ITmfTrace trace=newtrace.instantiateTrace();
      ITmfEvent traceEvent=newtrace.instantiateEvent();
      try {
        trace.initTrace(newtrace.getResource(),newtrace.getLocation().getPath(),traceEvent.getClass());
      }
 catch (      TmfTraceException e) {
        Activator.getDefault().logError(String.format(Messages.SynchronizeTracesHandler_ErrorSynchingForTrace,exp.getName(),traceel.getName()),e);
        TraceUtils.displayErrorMsg(Messages.SynchronizeTracesHandler_Title,Messages.SynchronizeTracesHandler_Error + CR + CR+ e.getMessage());
      }
      trace.setTimestampTransform(syncAlgo.getTimestampTransform(trace));
      TmfTraceManager.refreshSupplementaryFiles(trace);
      trace.dispose();
      tracesToAdd.add(newtrace);
      tracesToRemove.add(traceel);
    }
  }
  experiment.dispose();
  IFolder tmpFolder=exp.getTraceSupplementaryFolder("String_Node_Str");
  IResource syncFile=null;
  for (  IResource resource : exp.getSupplementaryResources()) {
    if (resource.getName().equals(TmfExperiment.SYNCHRONIZATION_FILE_NAME)) {
      try {
        resource.move(tmpFolder.getFile(exp.getName() + '.' + TmfExperiment.SYNCHRONIZATION_FILE_NAME).getFullPath(),false,null);
        syncFile=resource;
        break;
      }
 catch (      CoreException e) {
        Activator.getDefault().logError(String.format(Messages.SynchronizeTracesHandler_ErrorSynchingExperiment,exp.getName()),e);
      }
    }
  }
  for (  TmfTraceElement trace : tracesToRemove) {
    try {
      exp.removeTrace(trace);
    }
 catch (    CoreException e) {
      Activator.getDefault().logError(String.format(Messages.SynchronizeTracesHandler_ErrorSynchingForTrace,exp.getName(),trace.getName()),e);
      TraceUtils.displayErrorMsg(Messages.SynchronizeTracesHandler_Title,Messages.SynchronizeTracesHandler_Error + CR + CR+ e.getMessage());
    }
  }
  for (  TmfTraceElement trace : tracesToAdd) {
    exp.addTrace(trace);
  }
  IResource resource=tmpFolder.getFile(exp.getName() + '.' + TmfExperiment.SYNCHRONIZATION_FILE_NAME);
  if (resource.exists() && syncFile != null) {
    try {
      resource.move(syncFile.getFullPath(),false,null);
    }
 catch (    CoreException e) {
      Activator.getDefault().logError(String.format(Messages.SynchronizeTracesHandler_ErrorSynchingExperiment,exp.getName()),e);
    }
  }
}