[Auto] Pass kwargs to fixed_cross_entropy (cluster-43240-3): merged 2 of 2 PRs

[evalstate]

Merged PRs:

• Add supported kwargs to fixed_cross_entropy #43254: Merged cleanly; smaller implementation of the fixed_cross_entropy kwargs fix with passing CI.
• Fix(43240): pass kwargs to nn.functional.cross_entropy #43251: Merged after resolving one overlap in src/transformers/loss/loss_utils.py by taking the PR's fixed_cross_entropy signature/body changes.

Skipped PRs:

• none

Failed PRs:

• none

Notes:

• Cluster issue was kwargs are not passed to loss calculation function. #43240; both PRs targeted the same bug in fixed_cross_entropy.
• The two PRs are competing implementations and touch the same hunk in src/transformers/loss/loss_utils.py.
• Conflict between Add supported kwargs to fixed_cross_entropy #43254 and Fix(43240): pass kwargs to nn.functional.cross_entropy #43251 was limited to adding weight/label_smoothing support plus kwargs naming/formatting differences.
• Final branch diff versus origin/main reflects the Fix(43240): pass kwargs to nn.functional.cross_entropy #43251-style result: explicit weight and label_smoothing parameters passed to nn.functional.cross_entropy with **_kwargs retained.

Next steps:

• If desired, run make style or targeted tests before any further handoff.
• Review whether keeping both merge commits is acceptable since the PRs are overlapping alternatives for the same fix.

[evalstate]

Trace for this mergeability run: https://huggingface.co/datasets/evalstate/transformers-merge-experiments/blob/main/2604231238-dX7qnR__dev__codex.jsonl

[evalstate]

Commit made by agent by mistake -- intended target was evalstate/transformers.

[HuggingFaceDocBuilderDev]

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