Package: arpack
Severity: important
Tags: patch
Hi,
on the GNU Octave mailing list, the following issue was noted. It seems
that for some inputs, ARPACK causes a segfault in Octave.
The issue was first noted in 2006[1]. A patch was sent to ARPACK
upstream, but there never was an answer.
The issue came up again last year[2].
So, I'm asking you include the attached patch in ARPACK. A test program
(segtest.m) for Octave is included. It segfaults Octave with current
ARPACK, when called as segtest(100).
[1]
http://www-old.cae.wisc.edu/pipermail/octave-maintainers/2006-November/001230.html
[2] http://www-old.cae.wisc.edu/pipermail/bug-octave/2009-November/009818.html
BTW, I think there's something wrong with the orig tarball. It seems to
duplicate all source files and directories in a directory ARPACK.
Thanks
Thomas
-- System Information:
Debian Release: 5.0.3
APT prefers stable
APT policy: (500, 'stable')
Architecture: amd64 (x86_64)
Kernel: Linux 2.6.26-2-amd64 (SMP w/2 CPU cores)
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash
*** ARPACK.orig/SRC/dneupd.f 2000-09-20 22:58:34.000000000 +0200
--- ARPACK/SRC/dneupd.f 2006-11-03 11:27:21.159925329 +0100
***************
*** 353,359 ****
& mode , msglvl, outncv, ritzr ,
& ritzi , wri , wrr , irr ,
& iri , ibd , ishift, numcnv ,
! & np , jj
logical reord
Double precision
& conds , rnorm, sep , temp,
--- 353,359 ----
& mode , msglvl, outncv, ritzr ,
& ritzi , wri , wrr , irr ,
& iri , ibd , ishift, numcnv ,
! & np , jj , nconv2
logical reord
Double precision
& conds , rnorm, sep , temp,
***************
*** 661,676 ****
& workl(iuptri), ldh ,
& workl(invsub), ldq ,
& workl(iheigr), workl(iheigi),
! & nconv , conds ,
& sep , workl(ihbds) ,
& ncv , iwork ,
& 1 , ierr)
c
if (ierr .eq. 1) then
info = 1
go to 9000
end if
c
if (msglvl .gt. 2) then
call dvout (logfil, ncv, workl(iheigr), ndigit,
& '_neupd: Real part of the eigenvalues of H--reordered')
--- 661,681 ----
& workl(iuptri), ldh ,
& workl(invsub), ldq ,
& workl(iheigr), workl(iheigi),
! & nconv2 , conds ,
& sep , workl(ihbds) ,
& ncv , iwork ,
& 1 , ierr)
c
+ if (nconv2 .lt. nconv) then
+ nconv = nconv2
+ end if
+
if (ierr .eq. 1) then
info = 1
go to 9000
end if
c
+
if (msglvl .gt. 2) then
call dvout (logfil, ncv, workl(iheigr), ndigit,
& '_neupd: Real part of the eigenvalues of H--reordered')
*** ARPACK.orig/SRC/sneupd.f 2000-09-20 22:58:34.000000000 +0200
--- ARPACK/SRC/sneupd.f 2006-11-03 11:32:54.691913071 +0100
***************
*** 353,359 ****
& mode , msglvl, outncv, ritzr ,
& ritzi , wri , wrr , irr ,
& iri , ibd , ishift, numcnv ,
! & np , jj
logical reord
Real
& conds , rnorm, sep , temp,
--- 353,359 ----
& mode , msglvl, outncv, ritzr ,
& ritzi , wri , wrr , irr ,
& iri , ibd , ishift, numcnv ,
! & np , jj , nconv2
logical reord
Real
& conds , rnorm, sep , temp,
***************
*** 661,671 ****
& workl(iuptri), ldh ,
& workl(invsub), ldq ,
& workl(iheigr), workl(iheigi),
! & nconv , conds ,
& sep , workl(ihbds) ,
& ncv , iwork ,
& 1 , ierr)
c
if (ierr .eq. 1) then
info = 1
go to 9000
--- 661,675 ----
& workl(iuptri), ldh ,
& workl(invsub), ldq ,
& workl(iheigr), workl(iheigi),
! & nconv2 , conds ,
& sep , workl(ihbds) ,
& ncv , iwork ,
& 1 , ierr)
c
+ if (nconv2 .lt. nconv) then
+ nconv = nconv2
+ end if
+
if (ierr .eq. 1) then
info = 1
go to 9000
*** ARPACK.orig/SRC/zneupd.f 2002-08-15 07:51:12.000000000 +0200
--- ARPACK/SRC/zneupd.f 2006-11-03 11:33:28.032312460 +0100
***************
*** 301,307 ****
& invsub, iuptri, iwev , j , ldh , ldq ,
& mode , msglvl, ritz , wr , k , irz ,
& ibd , outncv, iq , np , numcnv, jj ,
! & ishift
Complex*16
& rnorm, temp, vl(1)
Double precision
--- 301,307 ----
& invsub, iuptri, iwev , j , ldh , ldq ,
& mode , msglvl, ritz , wr , k , irz ,
& ibd , outncv, iq , np , numcnv, jj ,
! & ishift, nconv2
Complex*16
& rnorm, temp, vl(1)
Double precision
***************
*** 592,600 ****
call ztrsen('None' , 'V' , select ,
& ncv , workl(iuptri), ldh ,
& workl(invsub), ldq , workl(iheig),
! & nconv , conds , sep ,
& workev , ncv , ierr)
c
if (ierr .eq. 1) then
info = 1
go to 9000
--- 592,604 ----
call ztrsen('None' , 'V' , select ,
& ncv , workl(iuptri), ldh ,
& workl(invsub), ldq , workl(iheig),
! & nconv2 , conds , sep ,
& workev , ncv , ierr)
c
+ if (nconv2 .lt. nconv) then
+ nconv = nconv2
+ end if
+
if (ierr .eq. 1) then
info = 1
go to 9000
*** ARPACK.orig/SRC/cneupd.f 2002-08-15 07:51:12.000000000 +0200
--- ARPACK/SRC/cneupd.f 2006-11-03 11:31:54.499802784 +0100
***************
*** 301,307 ****
& invsub, iuptri, iwev , j , ldh , ldq ,
& mode , msglvl, ritz , wr , k , irz ,
& ibd , outncv, iq , np , numcnv, jj ,
! & ishift
Complex
& rnorm, temp, vl(1)
Real
--- 301,307 ----
& invsub, iuptri, iwev , j , ldh , ldq ,
& mode , msglvl, ritz , wr , k , irz ,
& ibd , outncv, iq , np , numcnv, jj ,
! & ishift, nconv2
Complex
& rnorm, temp, vl(1)
Real
***************
*** 592,600 ****
call ctrsen('None' , 'V' , select ,
& ncv , workl(iuptri), ldh ,
& workl(invsub), ldq , workl(iheig),
! & nconv , conds , sep ,
& workev , ncv , ierr)
c
if (ierr .eq. 1) then
info = 1
go to 9000
--- 592,604 ----
call ctrsen('None' , 'V' , select ,
& ncv , workl(iuptri), ldh ,
& workl(invsub), ldq , workl(iheig),
! & nconv2 , conds , sep ,
& workev , ncv , ierr)
c
+ if (nconv2 .lt. nconv) then
+ nconv = nconv2
+ end if
+
if (ierr .eq. 1) then
info = 1
go to 9000
function aerr = segtest (iter)
%% This will seg-fault octave consistently, but not matlab.
n=20;
k=4;
A =
sparse([3:n,1:n,1:(n-2)],[1:(n-2),1:n,3:n],[ones(1,n-2),4*ones(1,n),-ones(1,n-2)]);
opts.disp = 0; opts.p = 19;
aerr = 0;
for i=1:iter
[v1,d1] = eigs(A, k, 'sr', opts);
d1 = diag(d1);
merr = 0;
for i=1:k
newerr = max(abs((A - d1(i)*speye(n))*v1(:,i)));
if (newerr > merr)
merr = newerr;
end
end
fprintf('Max Err: %g\n', merr);
if (merr > aerr)
aerr = merr;
end
end
end
