← Back to issue list

Trouble allocating fonts in a Tcl/Tk (Python 3.5) based snap

View original Launchpad issue

Metadata

Project
snapcraft (launchpad)
Number
#1709060
Type
issue
State
open
Author
~kushalchauhan98
Labels
python python3 tcl tkinter
Created
Updated
Closed
—

Current evaluation

Python3/Tkinter snap crashes with 'failed to allocate font due to internal system font engine problem' (or SEGFAULT) inside a snap while the same script works unsnapped; still open, no maintainer diagnosis.

Suggested action: keep open

Reason: The report is a real, reproducible defect class — a tkinter GUI snap that runs fine outside the snap fails at Label/Tk creation — and the last comment from ~eikekuehn42 (2019-10-08) reports the same failure mode on core18/snapcraft 3.8 plus a minimal reproducer (randomchars42/snap_python_tkinter_skeleton) and a companion open bug LP#1847321, so the class is not resolved. However, no maintainer has triaged or diagnosed it: the only evidence is two dead paste.ubuntu.com links and an external 2.33 snap, and the codebase has no tkinter/font-specific handling (only extension-level font plumbing such as gnome.py's "desktop": {"mount-host-font-cache": False}), so a fix would require fresh investigation against a current base.

Evaluated by: mr-cal-bot

Impact: 40 Quick Win: 5 Complexity: 65 Confidence: 62 Actionability: 35

Issue body

snapcraft version - 2.33 snap - https://github.com/kushalchauhan98/minimal-snip I am trying to snap a single python3 script. The code goes something like this: http://paste.ubuntu.com/25262415/ The python script (.py file) runs just fine when executed normally. But when I prime the snap and try it, I get this error on run: http://paste.ubuntu.com/25262438/ The font I am using in my app is the default one offered by tkinter. I haven't chosen any font explicitly to be used in my program. Initially, I was getting a error which I solved by referring to this question on AskUbuntu (https://askubuntu.com/questions/815511/setting-a-tcl-tk-library-path-inside-a-snap-package). But now, I am getting this error, which seems to be a snapcraft bug.

Evaluation history

Date Model Scores Action Summary
stealth/space-bunny-alpha
Impact: 40
Quick Win: 5
Complexity: 65
Confidence: 62
Actionability: 35
keep open Python3/Tkinter snap crashes with 'failed to allocate font due to internal system font engine problem' (or SEGFAULT) inside a snap while the same script works unsnapped; still open, no maintainer diagnosis.
stealth/space-bunny-alpha
Impact: 45
Quick Win: 6
Complexity: 68
Confidence: 72
Actionability: 45
needs triage Tkinter app in a python3 snap fails with '_tkinter.TCLError: failed to allocate font due to internal system font engine problem'; script works unsnapped. Reproducer is external paste links; a second user reports a similar SEGFAULT tracked in LP #1847321. No maintainer response.
qwen/qwen3.6-35b-a3b
Impact: 10
Quick Win: 0
Complexity: 10
Confidence: 80
Actionability: 0
close stale 9-year-old report of Tcl/Tk font allocation failure in a Python 3.5 snap using snapcraft 2.33. Zero comments, likely obsolete due to massive upstream changes.
qwen/qwen3.8-27b
Impact: 20
Quick Win: 12
Staleness: 95
Complexity: 40
Confidence: 75
Support Request: 55
close stale Tcl/Tk font allocation error when running a Python 3.5 tkinter snap built with snapcraft 2.33. No maintainer interaction; issue is 9 years old with zero comments.
qwen/qwen3.6-35b-a3b
Staleness: 98
Complexity: 25
Confidence: 92
Support Request: 75
close stale Packaging a Python 3.5 Tkinter app in snapcraft 2.33 fails with a Tcl/Tk font allocation error. The report is over 8 years old, uses deprecated tooling, and has no maintainer interaction.
qwen/qwen3.6-35b-a3b
Staleness: 98
Complexity: 25
Confidence: 90
Support Request: 75
close stale User reports a Tcl/Tk font allocation error when running a Python 3.5 snap built with snapcraft 2.33. The report has no maintainer comments, has been inactive for nearly seven years, and references long-deprecated software versions.
qwen3.6-35b-a3b-mtp-q6
Staleness: 95
Complexity: 25
Confidence: 90
Support Request: 70
close stale tkinter font allocation error when running a Python 3.5 script in a snap built with snapcraft 2.33. No maintainer response; issue is over 8 years old and references deprecated tool versions.

Update history

Date Change
created

Related work

  • Related To: snapcraft (launchpad)#1847321 (confidence 90%)

    ~eikekuehn42 explicitly opened LP#1847321 for the same tkinter-in-snap failure (SEGFAULT variant) and stated it 'might eventually be merged' with this bug; that bug is still open.

Related issues

Issue Project State Summary Similarity
#1847321 Snap with python3 + tkinter crashes with SEGFAULT snapcraft (launchpad) open Python3 + tkinter snap segfaults when creating a Label; minimal reproducer repo linked, but no diagnosis, no yaml shown, no maintainer response since 2019. Author cross-referenced LP#1709060; another user confirmed similar breakage in a 2020 forum thread.
70%