# alist[:] segfaults on centos 7 Jenkins

XMLWordPrintable

## Details

• Type: Bug
• Status: Won't Fix
• Resolution: Done
• Fix Version/s: None
• Component/s:
• Labels:

## Description

In line 146 of tests/testCoaddBoundedField.py using

 elements = self.elements[:] 

 elements = list(self.elements) 

causes a segfault on Jenkins, but only on centos7 running Python 2. It passes on centos 6 running Python 2. See https://ci.lsst.codes/job/stack-os-matrix/23424/label=centos-7,python=py2/console (The results of Mac builds are not yet known, as they are badly backed up.)

My suspicion is a bug in the gcc compiler used by Jenkins on centos 7. We plan to move to a newer compiler soon (using devtoolset) so this may not be worth spending a lot of time on.

## Activity

Hide
Russell Owen added a comment - - edited

I built the stack on macOS 10.12.4 using lsstsw and the included anaconda Python 2.7.13. Using list[:] in the unit test has not failed for me in over 20 executions.

We only have two Jenkins runs, which is not enough to be confident of anything, but both failed on centos 7 python 2 and both succeeded for the other two linux configurations (centos 7 python 3 and centos 6 python 2).

There is a ticket branch that shows the problem: u//rowen/trylistcolon in case you want to try it with Jenkins. This is branched from tickets/DM-9192 since DM 9192 is where the problem first appeared.

Show
Russell Owen added a comment - - edited I built the stack on macOS 10.12.4 using lsstsw and the included anaconda Python 2.7.13. Using list [:] in the unit test has not failed for me in over 20 executions. We only have two Jenkins runs, which is not enough to be confident of anything, but both failed on centos 7 python 2 and both succeeded for the other two linux configurations (centos 7 python 3 and centos 6 python 2). There is a ticket branch that shows the problem: u//rowen/trylistcolon in case you want to try it with Jenkins. This is branched from tickets/ DM-9192 since DM 9192 is where the problem first appeared.
Hide
John Parejko added a comment -

That branch has now been merged, so you can rebase to meas_algorithms master to test.

Show
John Parejko added a comment - That branch has now been merged, so you can rebase to meas_algorithms master to test.
Hide
Russell Owen added a comment - - edited

We only saw the problem using Python 2 and are no longer using that. I just made a new branch that uses elements[:] instead of list(elements) in test_coaddBoundedField.py and it does not show the problem on Jenkins (nor on my Mac). So I'm closing this as "won't fix".

Show
Russell Owen added a comment - - edited We only saw the problem using Python 2 and are no longer using that. I just made a new branch that uses elements [:] instead of list(elements) in test_coaddBoundedField.py and it does not show the problem on Jenkins (nor on my Mac). So I'm closing this as "won't fix".

## People

• Assignee:
Russell Owen
Reporter:
Russell Owen
Watchers:
John Parejko, Pim Schellart [X] (Inactive), Russell Owen