fix(linter): OOM problems with custom plugins

[overlookmotel]

This PR fixes OOM (Out of Memory) problems when using JS plugins together with the import plugin for cross-module analysis.

Previously, a stopgap solution simply refused to run when >10,000 files were linted with both features enabled.

This PR implements a real fix using a deferred cloning strategy: standard allocators are used for parsing/linting (efficient, dynamic sizing), and the AST is only copied into a fixed-size allocator briefly when calling JS plugins.

This dramatically reduces memory usage from n_files × 6 GiB to n_files × dynamic + thread_count × 6 GiB.

[Copilot]

Pull request overview

This PR addresses Out of Memory (OOM) issues that occur when using JavaScript plugins together with the import plugin for cross-module analysis. The implementation introduces a deferred cloning strategy that dramatically reduces memory usage.

Key Changes:

• Implements a dual-allocator strategy: standard allocators for parsing/linting, with AST cloning to fixed-size allocators only when calling JS plugins
• Removes the previous stopgap limitation that prevented linting >10,000 files with both features enabled
• Adds conditional compilation support to restrict JS plugin functionality to 64-bit little-endian platforms

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
crates/oxc_linter/src/service/runtime.rs	Adds separate js_allocator_pool field and logic to choose between standard and fixed-size allocators based on feature combination
crates/oxc_linter/src/lib.rs	Implements new clone_into_fixed_size_allocator_and_run_external_rules function for deferred cloning strategy and refactors external rule execution
crates/oxc_allocator/src/pool/fixed_size.rs	Removes ID wraparound assertion that is no longer needed
apps/oxlint/src/result.rs	Removes TooManyFilesWithImportAndJsPlugins error variant that is now obsolete
apps/oxlint/src/lint.rs	Removes the 10,000 file limit check and updates file system configuration logic for the new approach

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[codspeed-hq]

CodSpeed Performance Report

Merging #17082 will not alter performance

_{Comparing c/12-17-draft (feabf6e) with main (d209c21)}

Summary

✅ 42 untouched
⏩ 3 skipped¹

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩