new TFile *f; new TTree *t; ... delete t; delete f;

From: Alexander Zvyagin (zvyagin@mx.ihep.su)
Date: Mon Apr 27 1998 - 14:47:04 MEST 

                                           IHEP, Protvino, Russia, 27-APR-1998

Dear friends!

I have the following code:

{
  // Example 1

  TFile *root_file = new TFile("a.root","RECREATE", "file",9);
  TTree *tree      = new TTree("tree","tree");

  root_file->Write();
  root_file->Map();
  root_file->Print();
  root_file->Close();    // Close root file.

  delete tree;           // here!
  delete root_file;
}

produces next output:

TFile Writing Name=a.root Title=file
980427/160834  At:64        N=86        TFile         
980427/160835  At:150       N=104       TTree          CX =  2.71
980427/160835  At:254       N=90        TFile         
980427/160835  At:344       N=54        TFile         
TFile: name=a.root, title=file, option=CREATE
******************************************************************************
*Tree    :tree      : tree                                                   *
*Entries :        0 : Total  Size =       104 bytes  File  Size =        104 *
*        :          : Tree compression factor =   1.00                       *
******************************************************************************

 *** Break *** segmentation violation


Why "segmenation violation"?

If I remove  string  "delete tree;" the message
"*** Break *** segmentation violation" disappears.


The following code works well:

{
  // Example 2

  TFile root_file("a.root","RECREATE", "file",9);
  TTree tree("tree","tree");

  root_file->Write();
  root_file->Map();
  root_file->Print();
  root_file->Close();    // Close root file.
}


Why code 'Example 1' with new-delete operators is bad?

Thanks in advanced,
Alexander Zvyagin.

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