message: Add protection for the case of fallback on SPD vertex
diff: @@ -332,6 +332,7 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
  }
  if ((useSPDvtx) && (spdAvailable) && (!vertexerSPD3Doff)) {
  + printf("------> Fallback on SPD 3D vertexer <------\n");
  if(fShowPlots){
  TCanvas* cxs=new TCanvas("cxs","xSPDvertex");
  cxs->cd();
  @@ -526,7 +527,7 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
  histTRKVertexYZ = (TH2F*)file->Get("hITSSAVertexYZ");
  }
  }
  -
  + if(histTRKvsMultX && histTRKvsMultY && histTRKVertexXZ && histTRKVertexYZ){
  Int_t minprojbin=1;
  Int_t maxprojbin=300;
  if (highMultEnvironment) {
  @@ -679,6 +680,7 @@ void AliMeanVertexPreprocessorOffline::ProcessOutput(const char *filename, AliCD
  covarYZ = corrYZ*zSigmaVtx*zSigmaVtx;
  }
  }
  + }
  Double_t position[3], covMatrix[6];
  Double_t chi2=1.;
  