From octave-maintainers-request at bevo dot che dot wisc dot edu  Mon Nov  4 21:44:38 1996
Subject: QR causes random crashes...seg fault.
From: "John W. Eaton" <jwe at bevo dot che dot wisc dot edu>
To: Frederick (Rick) A Niles <niles at axp745 dot gsfc dot nasa dot gov>
Cc: octave-maintainers at bevo dot che dot wisc dot edu
Date: Mon, 4 Nov 1996 21:44:23 -0600

On  4-Nov-1996, Frederick A. Niles <niles at axp745 dot gsfc dot nasa dot gov> wrote:

: Description:
: -----------
: 
:   * If I do:
:         [Q, R, P] = qr (0)
:         several times under linux or OSF/1 I get:
: error: Segmentation fault -- stopping myself...
: attempting to save variables to `octave-core'...
: save to `octave-core' complete
: 
: Repeat-By:
: ---------
: 
:   * Doing the same, but note:
:         1) I think you need three return items.
: 	2) In an m-file with other stuff it's worse.
: 	3) This could be a general problem with all oct-files!

Luckily, I think it is just a brain-o with the implementation of the
QRP classes.

jwe


Index: dbleQRP.cc
===================================================================
RCS file: /home/jwe/src/master/octave/liboctave/dbleQRP.cc,v
retrieving revision 1.16
diff -c -r1.16 dbleQRP.cc
*** dbleQRP.cc	1996/03/03 01:16:15	1.16
--- dbleQRP.cc	1996/11/05 03:37:12
***************
*** 140,146 ****
  	(*current_liboctave_error_handler) ("unrecoverable error in dorgqr");
        else
  	{
! 	  q = Matrix (tmp_data, m, m);
  	  q.resize (m, n2);
  	}
      }
--- 140,146 ----
  	(*current_liboctave_error_handler) ("unrecoverable error in dorgqr");
        else
  	{
! 	  q = A_fact;
  	  q.resize (m, n2);
  	}
      }
Index: CmplxQRP.cc
===================================================================
RCS file: /home/jwe/src/master/octave/liboctave/CmplxQRP.cc,v
retrieving revision 1.16
diff -c -r1.16 CmplxQRP.cc
*** CmplxQRP.cc	1996/03/03 01:16:15	1.16
--- CmplxQRP.cc	1996/11/05 03:37:33
***************
*** 145,151 ****
  	(*current_liboctave_error_handler) ("unrecoverable error in zungqr");
        else
  	{
! 	  q = ComplexMatrix (tmp_data, m, m);
  	  q.resize (m, n2);
  	}
      }
--- 145,151 ----
  	(*current_liboctave_error_handler) ("unrecoverable error in zungqr");
        else
  	{
! 	  q = A_fact;
  	  q.resize (m, n2);
  	}
      }