[Pkg-octave-devel] Bug#783034: octave-ltfat breaks Octave rcond. Yields segmentation fault

[Charlie Hagedorn]

Package: octave-ltfat
Version: 2.0.1-1
Severity: important

Dear Maintainer,

I've had inconsistent Octave seg-faults on several jessie machines that I've traced to at least the octave-ltfat package. The seg-faults are triggered calls to the Octave function rcond. Installing octave-ltfat makes it break, uninstalling restores expected behavior (i.e. not crashing Octave).

I discovered this problem when chasing down a segmentation fault in octave-optim's leasqr function. rcond breaks only on matrices of size greater than 9 (31 is used below), so it will only turn up when fitting functions of ten or more parameters. 

Example breakage: 

cah49 at charlie:~$ octave --quiet
octave:1> rcond(magic(31))
ans =  0.030391
octave:2> cah49 at charlie:~$ 
cah49 at charlie:~$ sudo apt-get install octave-ltfat
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following NEW packages will be installed:
  octave-ltfat
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/561 kB of archives.
After this operation, 7,074 kB of additional disk space will be used.
Selecting previously unselected package octave-ltfat.
(Reading database ... 100497 files and directories currently installed.)
Preparing to unpack .../octave-ltfat_2.0.1-1_amd64.deb ...
Unpacking octave-ltfat (2.0.1-1) ...
Setting up octave-ltfat (2.0.1-1) ...
cah49 at charlie:~$ octave --quiet
octave:1> rcond(magic(31))
Segmentation fault
cah49 at charlie:~$ sudo apt-get remove octave-ltfat
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  octave-ltfat-common
Use 'apt-get autoremove' to remove it.
The following packages will be REMOVED:
  octave-ltfat
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
After this operation, 7,074 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 100544 files and directories currently installed.)
Removing octave-ltfat (2.0.1-1) ...
cah49 at charlie:~$ octave --quiet
octave:1> rcond(magic(31))
ans =  0.030391
octave:2> 

I will update this bug report if I find any other packages that break 
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-- System Information:
Debian Release: 8.0
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 3.16.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages octave-ltfat depends on:
ii  libblas3 [libblas.so.3]            1.2.20110419-10
ii  libc6                              2.19-18
ii  libfftw3-double3                   3.3.4-2
ii  libfftw3-single3                   3.3.4-2
ii  libgcc1                            1:4.9.2-10
ii  libgfortran3                       4.9.2-10
ii  liblapack3 [liblapack.so.3]        3.5.0-4
ii  liboctave2                         3.8.2-4
ii  libopenblas-base [liblapack.so.3]  0.2.12-1
ii  libquadmath0                       4.9.2-10
ii  libstdc++6                         4.9.2-10
ii  octave                             3.8.2-4
ii  octave-ltfat-common                2.0.1-1

octave-ltfat recommends no packages.

octave-ltfat suggests no packages.

-- no debconf information