Opened 5 years ago
Closed 4 years ago
#21391 closed enhancement (duplicate)
Disallow mixing of pos.char.ring elements and symbolic variables
Reported by:  rws  Owned by:  

Priority:  critical  Milestone:  sageduplicate/invalid/wontfix 
Component:  symbolics  Keywords:  segfault 
Cc:  jdemeyer, vdelecroix, slelievre  Merged in:  
Authors:  Reviewers:  Ralf Stephan  
Report Upstream:  N/A  Work issues:  
Branch:  u/rws/disallow_mixing_of_pos_char_ring_elements_and_symbolic_variables (Commits, GitHub, GitLab)  Commit:  8de83982441dd28b52f6f544218d48431381d8d9 
Dependencies:  Stopgaps: 
Description (last modified by )
This is to have a place for code examples and discussion of impact of the proposal in https://groups.google.com/forum/?hl=en#!topic/sagedevel/auLwQWtpnz0
The following produces a segmentation fault (Sage 7.4, Ubuntu 14.04 or OS X 10.10.5), see Ask Sage.
sage: F = GF(3) sage: num, den = F(2)*x + F(1), x sage: num/den ... segmentation fault ...
With this branch this gives: TypeError: Multiplication of symbolic variable and an element of a ring with positive characteristic.
See also sagesupport.
Change History (17)
comment:1 Changed 5 years ago by
 Branch set to u/rws/disallow_mixing_of_pos_char_ring_elements_and_symbolic_variables
comment:2 Changed 5 years ago by
 Cc jdemeyer vdelecroix added
 Commit set to 7147699e66955b2a130a871b97886ec5af3a665d
comment:3 Changed 5 years ago by
Alternatively this could be made a stopgap. Which is better?
comment:4 Changed 5 years ago by
 Cc slelievre added
 Description modified (diff)
 Keywords segfault added
Adding an example leading to a segmentation fault to the ticket description.
comment:5 Changed 5 years ago by
 Description modified (diff)
comment:6 Changed 5 years ago by
 Description modified (diff)
 Milestone changed from sage7.4 to sage7.6
comment:7 Changed 5 years ago by
 Commit changed from 7147699e66955b2a130a871b97886ec5af3a665d to f2933cc95f5ace319d93038c92bd92e9b6e3e3ac
Branch pushed to git repo; I updated commit sha1. New commits:
dd6ad96  Merge branch 'develop' into t/21391/disallow_mixing_of_pos_char_ring_elements_and_symbolic_variables

03ccd07  Merge branch 'develop' into t/21391/disallow_mixing_of_pos_char_ring_elements_and_symbolic_variables

f2933cc  21391: introduce ex.has_finite_parent()

comment:8 Changed 5 years ago by
 Status changed from new to needs_review
comment:9 Changed 5 years ago by
 Priority changed from major to critical
Critical because of segfault and public interest.
comment:10 Changed 4 years ago by
 Commit changed from f2933cc95f5ace319d93038c92bd92e9b6e3e3ac to 333db3c0de1e767304a8b9be2e2894038d0b3cbd
Branch pushed to git repo; I updated commit sha1. New commits:
333db3c  Merge branch 'develop' into t/21391/disallow_mixing_of_pos_char_ring_elements_and_symbolic_variables

comment:12 Changed 4 years ago by
 Commit changed from 333db3c0de1e767304a8b9be2e2894038d0b3cbd to 9430605a17f8793efff5453966fea424e28423a0
comment:13 Changed 4 years ago by
 Status changed from needs_work to needs_review
comment:14 Changed 4 years ago by
 Commit changed from 9430605a17f8793efff5453966fea424e28423a0 to 8de83982441dd28b52f6f544218d48431381d8d9
Branch pushed to git repo; I updated commit sha1. New commits:
8de8398  Merge branch 'develop' into t/21391/disallow_mixing_of_pos_char_ring_elements_and_symbolic_variables

comment:15 Changed 4 years ago by
 Milestone changed from sage7.6 to sage8.1
 Status changed from needs_review to needs_work
Doctest failures.
comment:16 Changed 4 years ago by
 Milestone changed from sage8.1 to sageduplicate/invalid/wontfix
 Status changed from needs_work to needs_review
I think this can be closed as duplicate since #24072 has positive review.
comment:17 Changed 4 years ago by
 Resolution set to duplicate
 Reviewers set to Ralf Stephan
 Status changed from needs_review to closed
In a first scan these doctests would have to be changed:
New commits:
21391: Disallow mixing of pos.char.ring elements and symbolic variables