unhelpful error when building a classic snap: classic confinement requires the core_dynamic_linker to be set
Metadata
Current evaluation
Resolved: the cryptic "classic confinement requires the core_dynamic_linker to be set" error was fixed by snapcore/snapcraft PR #1025 (better diagnostic) and PR #1112 / commit 49b39ef9a, which auto-installs/unpacks the core snap; Launchpad builds snapcraft 2.27+ via LP: #1650946.
Resolution: closed resolved
Reason: Merged snapcore/snapcraft#1025 improved the missing-core error message, and #1112 (commit 49b39ef9a, "core: setup core to support classic confinement") made snapcraft fetch/unpack the core snap automatically. buildsnapped changelog confirms launchpad-buildd now sets SNAPCRAFT_SETUP_CORE=1, with cjwatson reporting the fix lands in snapcraft 2.27 in -updates.
Evaluated by: mr-cal-bot
No scores available.
Issue body
I got this error when trying to snap the git demo in xenial 16.04:
classic confinement requires the core_dynamic_linker to be set
And then I have no idea what else to do.
The error message should explain a little more about what it's missing, and how to get it.
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| stealth/space-bunny-alpha | — | closed resolved | Resolved: the cryptic "classic confinement requires the core_dynamic_linker to be set" error was fixed by snapcore/snapcraft PR #1025 (better diagnostic) and PR #1112 / commit 49b39ef9a, which auto-installs/unpacks the core snap; Launchpad builds snapcraft 2.27+ via LP: #1650946. | |
| stealth/space-bunny-alpha | — | closed resolved | Merged PR #1025 (bfe41e68c) improved the missing-core diagnostic; automatic core setup also landed in #1112 (49b39ef9a), with Launchpad support reported in Snapcraft 2.27. | |
| stealth/space-bunny-alpha | — | closed resolved | Resolved by merged PR canonical/snapcraft#1025 (bfe41e68c), which improved the missing-core error shown while building classic snaps. | |
| qwen/qwen3.6-35b-a3b | — | — | Abandoned due to age and zero comments. The request to improve error messaging for missing core_dynamic_linker in classic snaps received no resolution. | |
| qwen/qwen3.6-35b-a3b | — | — | Abandoned and closed without resolution or comments. The reporter requested a more descriptive error message for missing core_dynamic_linker during classic snap builds, but no fix or response was provided. |
Update history
| Date | Change |
|---|---|
| created |
Related work
-
Likely Fixed By:
snapcore/snapcraft#1025
(confidence 90%)
PR referenced by sergiusens to fix the ugly error message when the core snap is missing
-
Likely Fixed By:
snapcore/snapcraft#1112
(confidence 90%)
Commit 49b39ef9a 'core: setup core to support classic confinement' automates fetching/unpacking core
-
Related To:
snapcore/snapcraft#1170
(confidence 45%)
Follow-up fix for core_dynamic_linker symlink resolution (commit b19e9cf68)
Related issues
| Issue | Project | State | Summary | Similarity |
|---|---|---|---|---|
| #1170 core: fix symlink resolution in get_core_dynamic_linker | snapcraft | merged | Merged canonical/snapcraft#1170 as commit b19e9cf68, fixing relative symlink resolution in get_core_dynamic_linker so classic snap builds work on affected architectures. | |
| #1665165 classic snaps fail to build in launchpad in archs other than amd64 | snapcraft (launchpad) | closed | Classic non-amd64 Launchpad builds were fixed by snapcraft PR #1170 (commit b19e9cf68), correcting relative core dynamic-linker symlink resolution. | |
| #1647422 Support classic confinement | snapcraft (launchpad) | closed | Classic confinement support was implemented and merged in snapcore/snapcraft#946 via commit 97af16ffe, resolving launchpad/snapcraft#1647422. | |
| #1112 core: setup core to support classic confinement. | snapcraft | merged | Merged PR #1112 (49b39ef9a) added SNAPCRAFT_SETUP_CORE, fetching and unsquashing core into expected paths for classic-confinement builds on non-Snappy CI hosts. | |
| #1025 project loader: better error message for classic | snapcraft | merged | Merged PR #1025 as commit bfe41e68c, clarifying the project-loader error when classic confinement requires a core snap that is missing. | |
| #1665081 building a classic snap does'nt remove /snap/core/current | snapcraft (launchpad) | closed | Closed without a code fix; the maintainer clarified that SNAPCRAFT_SETUP_CLASSIC=1 is only intended for CI use. | |
| #1665089 snapcraft 2.27 fails to build the mosh classic snap | snapcraft (launchpad) | closed | Resolved by snapcraft#1146, restoring reverted libc symlinks needed for classic-confinement builds such as mosh. Merged as commit 0f4872241. | |
| #1752957 Building classic snap without core snap installed succeeds, but creates snap that doesn't run | snapcraft (launchpad) | open | Legacy Snapcraft 2.x classic builds could emit a non-running snap when core was absent; the affected base and implementation are now obsolete. | |
| #288 snap: strict -> classic confinement for Charmcraft snap | charmcraft | merged | Merged (commit d49e85e3, merge 0d76670a): switched Charmcraft's snap from strict to classic confinement, added a separate part for core20 Python stage packages, and hardcoded bin/python3 to work around a Snapcraft symlink bug. |