[BUG] Fixed uninitialized FJ constraint weights when the problem grows

[nguidotti]

When the feasibility pump adds the objective cutting plane to the problem, fj.solve() resizes the constraint weights, but leave the new weights unintialized. This trips the assertion that checks for infinite (and a negative) weights in the GPU FJ. The solution is to set the new weights to 1.0, which matches copy_weights and cstr_weights fixup in do_fj_solve. Note that fj.solve() bypasses do_fj_solve.

Checklist

• I am familiar with the Contributing Guidelines.
• Testing
  • New or existing tests cover these changes
  • Added tests
  • Created an issue to follow-up
  • NA
• Documentation
  • The documentation is up to date with these changes
  • Added new documentation
  • NA

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📥 Commits

Reviewing files that changed from the base of the PR and between 6df36e2 and 1a4c4a6.

📒 Files selected for processing (1)

• cpp/src/mip_heuristics/feasibility_jump/feasibility_jump.cu

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📝 Walkthrough

Walkthrough

resize_vectors now preserves existing constraint weights and initializes newly added primary, left, and right entries to 1.0.

Changes

Feasibility jump constraint weights

Layer / File(s)	Summary
Preserve and initialize constraint weights cpp/src/mip_heuristics/feasibility_jump/feasibility_jump.cu	resize_vectors preserves existing weights during resizing and initializes new entries in the primary, left, and right arrays to 1.0.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested reviewers: akifcorduk, aliceb-nv, rg20

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the bug and the fix for uninitialized feasibility pump constraint weights when the problem grows.
Description check	✅ Passed	The description directly explains the defect, its cause, the fix, and related testing and documentation status.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[aliceb-nv]

Thanks for the quick fix Nicolas!

[github-actions]

CI Test Summary

✅ All 31 test job(s) passed.

[nguidotti]

/merge