[Bug 429015] Re: python-visual seg faults even in simple test cases

[gs]

*** This bug is a duplicate of bug 457688 ***
    https://bugs.launchpad.net/bugs/457688

This bug is still present in Lucid beta2 (64bit). See new bug #560297
for details.

Tested on computer with ati graphics, but hardware acceleration not
installed.

-- 
python-visual seg faults even in simple test cases
https://bugs.launchpad.net/bugs/429015
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Status in “python-visual” package in Ubuntu: New

Bug description:
Binary package hint: python-visual

Test case 1:

Observed outcome 

~ $python
Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from visual import *
>>> v = vector('x')
Segmentation fault

Expected outcome (output from 8.04.3)

u9 at test:~$ python
Python 2.5.2 (r252:60911, Jul 31 2008, 17:31:22) 
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from visual import *
>>> v = vector('x')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: Vectors must be constructed from sequences of 2 or 3 float members.
>>> 

Test case 2:

Observed outcome 

~ $python
Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from visual import *
>>> v=vector(1,2,3)
>>> for i in v:
...     print i
... 
1.0
2.0
3.0
Segmentation fault

Expected outcome (output from 8.04.3)

u9 at test:~$ python
Python 2.5.2 (r252:60911, Jul 31 2008, 17:31:22) 
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from visual import *
>>> v=vector(1,2,3)
>>> for i in v:
...     print i
... 
1.0
2.0
3.0
>>> 

Ubuntu releases tested:

Error occurs on 9.04 32bit, 9.04 64bit,, 8.10 64bit
Error does not occur on 8.04 32bit,  8.04 64bit
Not tested 8.10 32bit

How to reproduce:

Clean install from CD
aptitude update
aptitude safe-upgrade (this step  is optional, has no effect on outcome, positive or negative)
aptitude install python-visual
(Important! Do not activate proprietary graphics driver.)
run test as shown above

What happens if one activates proprietary graphics driver (For these tests I used the menu option to install the drivers):

No change with ATI/AMD graphics cards. Errors (seg faults) occur exactly the same as without the  proprietary graphics driver.

With Nvidia graphics cards test 1 and 2 do not seg fault.

Reproducibility (hardware tested):

6 different computers (2xnvidia graphics, 4x ATI/AMD graphics) 1 Dell, 1 Dell laptop, 1 Lenovo laptop, 3 different custom builds.

A third test case has slightly different behavior:

Test case 3:

Observed outcome 

~ $python
Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from visual import *
>>> quit()
Segmentation fault

Expected outcome:

~ $python
Python 2.6.2 (release26-maint, Apr 19 2009, 01:58:18) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from visual import *
>>> quit()
~ $

Test case 3 works on 8.04.3 AND 8.10, but fails on 9.04. Unlike test case 1 and 2 installing proprietary graphics drivers on systems with nvidia graphics does not change the negative outcome.

This last error is less severe than the first two, because it happens when exciting the python interpreter. Still it is very annoying.

Additional remarks:

Same behavior for new upstream version (5.12_release), compiled from source.

python-visual is used heavily with novice programmers and a seg fault instead of an error message for a simple syntax error is deadly.

python-visual on debian lenny works on all tested hardware.