RooDataSet* GetData(RooRealVar &x)
{
  TFile *rootFile = new TFile("test.root","READ");
  TTree *tree = (TTree*)rootFile->Get("tree");
  RooDataSet *data = new RooDataSet("data","data",tree,RooArgSet(x));
  delete rootFile;
  rootFile = 0;
  return data;
}

void DeleteData(RooDataSet *data)
{
  delete data;
  data = 0;
}

RooAbsPdf* GetPdf(RooRealVar &x)
{
  RooRealVar a("a","a",450.,250.,650.);
  RooRealVar b("b","b",125.,50.,200.);
  RooAbsPdf *pdf = new RooGaussian("pdf","pdf",x,a,b);
  return pdf;
}

void DeletePdf(RooAbsPdf *pdf)
{
  delete pdf;
  pdf = 0;
}

void test()
{
  RooRealVar x("numDegDaysBranch","numDegDaysBranch",190.,785.);
  RooAbsPdf *pdf = GetPdf(x);

  ////////// If I move the following block of code into GetPdf(), above, it works //////////
  RooDataSet *data = GetData(x);
  pdf->fitTo(*data);                                 // Crashes at this line, when in test()
  RooPlot *xframe = x.frame();
  data->plotOn(xframe);
  pdf->plotOn(xframe);
  xframe->Draw();
  //////////////////////////////////////////////////////////////////////////////////////////

  DeletePdf(pdf);
  DeleteData(data);
}