[tadeja]

Rationale for this change

Closes #55416

What changes are included in this PR?

Update C++ Emscripten from 3.1.45 to 5.0.3 ( and remove the offset-converter workaround for Emscripten<4.0.14 )

Are these changes tested?

Yes

Are there any user-facing changes?

No

Was AI used for this PR?

PR code and description written by:

• Human
• AI

Reviewed before submission by:

• Human
• AI
• Not reviewed

• GitHub Issue: [CI][C++] Update Emscripten to 5.0.3 #55416

[github-actions]

⚠️ GitHub issue #55416 has been automatically assigned in GitHub to PR creator.

[tadeja]

@github-actions crossbow submit *-emscripten

[github-actions]

Revision: 8ba3527

Submitted crossbow builds: ursacomputing/crossbow @ actions-c3b963985d

Task	Status
test-conda-python-emscripten
test-ubuntu-22.04-cpp-emscripten

[Copilot]

🟢 Approval recommended

No active review issues are reported for the C++ CI Emscripten update and removal of the legacy workaround.

No open issues 🎉

What changed in this PR

Updates Emscripten for the C++ Ubuntu 22.04 nightly CI job, addressing #55416. The separate Python/Pyodide toolchain update remains out of scope.

Changes:

• Bumps the C++ CI image’s Emscripten version from 3.1.45 to 5.0.3.
• Removes the offset-converter workaround for Emscripten versions older than 4.0.14.

File	Description
cpp/​cmake_modules/​SetupCxxFlags.cmake	Removes the legacy Emscripten offset-converter linker flag.
ci/​docker/​ubuntu-22.04-cpp.dockerfile	Updates the default Emscripten version to 5.0.3.

_{Review effort: Balanced}