fix: handle directories in dep-info source file hashing by mmastrac · Pull Request #2676 · mozilla/sccache

mmastrac · 2026-04-17T17:49:14Z

This patch has been in testing in the vercel/sccache fork for a number of weeks.

When proc_macro::tracked::path() registers a directory as a dependency, rustc's dep-info output includes the directory path. sccache previously crashed with "Is a directory" when trying to hash these paths.

Now recursively hashes all files within the directory (sorted for determinism), using relative paths as delimiters. This correctly captures directory dependencies so cache invalidation works when any file in the tracked directory changes.

Note that proc_macro_tracked_path is a nightly-only feature, but this nightly feature is being used by an include_dirs fork used by the next.js team. The hashing falls back to the same file-specific hash as before in all other cases.

Fixes: #2653

When proc_macro::tracked::path() registers a directory as a dependency, rustc's dep-info output includes the directory path. sccache previously crashed with "Is a directory" when trying to hash these paths. Now recursively hashes all files within the directory (sorted for determinism), using relative paths as delimiters. This correctly captures directory dependencies so cache invalidation works when any file in the tracked directory changes. Fixes: mozilla#2653

codecov-commenter · 2026-04-23T07:57:48Z

Codecov Report

❌ Patch coverage is 95.65217% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 74.25%. Comparing base (d11e2e0) to head (b19aa5e).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
src/util.rs	95.65%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2676      +/-   ##
==========================================
+ Coverage   74.17%   74.25%   +0.08%     
==========================================
  Files          70       70              
  Lines       39207    39325     +118     
==========================================
+ Hits        29083    29202     +119     
+ Misses      10124    10123       -1

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

codspeed-hq · 2026-04-24T06:46:49Z

Merging this PR will not alter performance

✅ 60 untouched benchmarks
⏩ 4 skipped benchmarks¹

_{Comparing vercel:upstream-pr/fix-dir-dep-info (b19aa5e) with main (b81fdbb)}

4 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. ↩

sylvestre · 2026-04-28T11:08:25Z

thanks

….0) (#40) This PR contains the following updates: | Package | Update | Change | |---|---|---| | [mozilla/sccache](https://github.com/mozilla/sccache) | minor | `0.14.0` → `0.15.0` | --- ### Release Notes <details> <summary>mozilla/sccache (mozilla/sccache)</summary> ### [`v0.15.0`](https://github.com/mozilla/sccache/releases/tag/v0.15.0) [Compare Source](mozilla/sccache@v0.14.0...v0.15.0) ##### sccache 0.15.0 ##### Summary sccache 0.15.0 brings several notable improvements: - **Multi-tier caching**: New support for layered caches with fallback and automatic backfilling between tiers ([#2581](mozilla/sccache#2581)). - **C++20 modules**: Initial (partial) support for compiling C++20 modules ([#2516](mozilla/sccache#2516)). - **Expanded MSVC support**: New flags handled including `d1nodatetime`, `await:strict` ([#2617](mozilla/sccache#2617)), `Y-`, `YI`, `Zf` ([#2663](mozilla/sccache#2663)), and the default `.pdb` extension for `/Fd` ([#2621](mozilla/sccache#2621)). - **New platforms**: loongarch64 support ([#2669](mozilla/sccache#2669)) and `crt-static` for riscv64 musl targets ([#2683](mozilla/sccache#2683)). - **ccache interop**: Avoid double-caching when ccache is also installed in `PATH` ([#2524](mozilla/sccache#2524)). - **Cargo integration**: `CARGO_ENCODED_RUSTFLAGS` is now excluded from the env var hash to prevent spurious cache misses ([#2651](mozilla/sccache#2651)), and dep-info handling correctly skips directories ([#2676](mozilla/sccache#2676)). - **Distribution**: cargo-binstall metadata for prebuilt binary installation ([#2647](mozilla/sccache#2647)). - **Reliability fixes**: GCS initialization ([#2637](mozilla/sccache#2637)), Windows `Win32_Security` feature ([#2627](mozilla/sccache#2627)), and retries for dist docker image builds ([#2677](mozilla/sccache#2677)). This release also includes a large round of clippy-driven cleanups and several CI fixes. Welcome to 7 new contributors! ##### Features - Avoid double-caching when ccache is installed in PATH by [@avikivity](https://github.com/avikivity) in [#2524](mozilla/sccache#2524) - partial c++20 module support by [@TroyKomodo](https://github.com/TroyKomodo) in [#2516](mozilla/sccache#2516) - Add support for `d1nodatetime` & `await:strict` MSVC flags by [@AJIOB](https://github.com/AJIOB) in [#2617](mozilla/sccache#2617) - msvc: Append the default .pdb extension for the /Fd argument by [@ikolomiko](https://github.com/ikolomiko) in [#2621](mozilla/sccache#2621) - msvc: add support for Y-, YI, Zf flags by [@AJIOB](https://github.com/AJIOB) in [#2663](mozilla/sccache#2663) - Implement multiple tiers caching with fallback and backfilling by [@Felixoid](https://github.com/Felixoid) in [#2581](mozilla/sccache#2581) - feat: Add loongarch64 support by [@wojiushixiaobai](https://github.com/wojiushixiaobai) in [#2669](mozilla/sccache#2669) - Add cargo-binstall metadata for prebuilt binary installation by [@sylvestre](https://github.com/sylvestre) in [#2647](mozilla/sccache#2647) ##### Fixes - fix: add Win32\_Security feature to windows-sys dependency by [@JulienCote](https://github.com/JulienCote) in [#2627](mozilla/sccache#2627) - Fix GCS initialization by [@msuozzo](https://github.com/msuozzo) in [#2637](mozilla/sccache#2637) - fix: exclude `CARGO_ENCODED_RUSTFLAGS` from env var hash by [@weihanglo](https://github.com/weihanglo) in [#2651](mozilla/sccache#2651) - fix: handle directories in dep-info source file hashing by [@mmastrac](https://github.com/mmastrac) in [#2676](mozilla/sccache#2676) ##### CI - Revert "actions: add security audit workflow" by [@sylvestre](https://github.com/sylvestre) in [#2603](mozilla/sccache#2603) - ci: fix artifact\_failure action when target dir does not exist by [@sylvestre](https://github.com/sylvestre) in [#2635](mozilla/sccache#2635) - ci: set crt-static for riscv64 musl targets by [@wojiushixiaobai](https://github.com/wojiushixiaobai) in [#2683](mozilla/sccache#2683) - Add retry for dists docker image build by [@Felixoid](https://github.com/Felixoid) in [#2677](mozilla/sccache#2677) ##### Clippy & cleanup - clippy: fix cloned\_ref\_to\_slice\_refs lint by [@xtqqczze](https://github.com/xtqqczze) in [#2602](mozilla/sccache#2602) - clippy: fix semicolon\_if\_nothing\_returned lint by [@xtqqczze](https://github.com/xtqqczze) in [#2601](mozilla/sccache#2601) - clippy: fix cloned\_instead\_of\_copied lint by [@xtqqczze](https://github.com/xtqqczze) in [#2605](mozilla/sccache#2605) - clippy: fix explicit\_into\_iter\_loop lint by [@xtqqczze](https://github.com/xtqqczze) in [#2616](mozilla/sccache#2616) - clippy: fix unnecessary\_semicolon lint by [@xtqqczze](https://github.com/xtqqczze) in [#2615](mozilla/sccache#2615) - clippy: fix manual\_string\_new lint by [@xtqqczze](https://github.com/xtqqczze) in [#2609](mozilla/sccache#2609) - clippy: fix ptr\_as\_ptr lint by [@xtqqczze](https://github.com/xtqqczze) in [#2611](mozilla/sccache#2611) - clippy: fix ref\_option lint by [@xtqqczze](https://github.com/xtqqczze) in [#2608](mozilla/sccache#2608) - clippy: fix from\_iter\_instead\_of\_collect lint by [@xtqqczze](https://github.com/xtqqczze) in [#2614](mozilla/sccache#2614) - Move PreprocessorCacheModeConfig to src/config.rs by [@xis19](https://github.com/xis19) in [#2604](mozilla/sccache#2604) - Remove benchmark normalize\_win\_path\_utf8 by [@sylvestre](https://github.com/sylvestre) in [#2634](mozilla/sccache#2634) - Move cmake-modules to integration tests by [@Felixoid](https://github.com/Felixoid) in [#2649](mozilla/sccache#2649) ##### Docs - docs(Rust.md): Add caveats from README by [@TheJanzap](https://github.com/TheJanzap) in [#2684](mozilla/sccache#2684) ##### Dependencies - chore: switch thirtyfour\_sync to thirtyfour by [@tottoto](https://github.com/tottoto) in [#2613](mozilla/sccache#2613) - build(deps): bump actions/upload-artifact from 4 to 7 by [@dependabot](https://github.com/dependabot)\[bot] in [#2632](mozilla/sccache#2632) - build(deps): bump actions/download-artifact from 5 to 8 by [@dependabot](https://github.com/dependabot)\[bot] in [#2631](mozilla/sccache#2631) - chore(deps): update rust crate quinn-proto to v0.11.14 by [@xtqqczze](https://github.com/xtqqczze) in [#2645](mozilla/sccache#2645) ##### New Contributors - [@ikolomiko](https://github.com/ikolomiko) made their first contribution in [#2621](mozilla/sccache#2621) - [@JulienCote](https://github.com/JulienCote) made their first contribution in [#2627](mozilla/sccache#2627) - [@msuozzo](https://github.com/msuozzo) made their first contribution in [#2637](mozilla/sccache#2637) - [@weihanglo](https://github.com/weihanglo) made their first contribution in [#2651](mozilla/sccache#2651) - [@wojiushixiaobai](https://github.com/wojiushixiaobai) made their first contribution in [#2669](mozilla/sccache#2669) - [@TheJanzap](https://github.com/TheJanzap) made their first contribution in [#2684](mozilla/sccache#2684) - [@mmastrac](https://github.com/mmastrac) made their first contribution in [#2676](mozilla/sccache#2676) **Full Changelog**: <mozilla/sccache@v0.14.0...v0.15.0> </details> --- ### Configuration 📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this PR, check this box --- This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).  Reviewed-on: https://git.erwanleboucher.dev/eleboucher/towonel/pulls/40

mmastrac force-pushed the upstream-pr/fix-dir-dep-info branch from 5e7caa4 to 0e3a517 Compare April 17, 2026 17:52

mmastrac force-pushed the upstream-pr/fix-dir-dep-info branch from 0e3a517 to 3a3f315 Compare April 17, 2026 18:20

Fix coverage

b19aa5e

sylvestre merged commit 00c8126 into mozilla:main Apr 28, 2026
52 checks passed

BrewTestBot mentioned this pull request Apr 29, 2026

sccache 0.15.0 Homebrew/homebrew-core#280093

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

fix: handle directories in dep-info source file hashing#2676

fix: handle directories in dep-info source file hashing#2676
sylvestre merged 2 commits into
mozilla:mainfrom
vercel:upstream-pr/fix-dir-dep-info

mmastrac commented Apr 17, 2026 •

edited

Loading

Uh oh!

codecov-commenter commented Apr 23, 2026 •

edited

Loading

Uh oh!

codspeed-hq Bot commented Apr 24, 2026 •

edited

Loading

Uh oh!

Uh oh!

sylvestre commented Apr 28, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

mmastrac commented Apr 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

codecov-commenter commented Apr 23, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Codecov Report

Uh oh!

codspeed-hq Bot commented Apr 24, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Merging this PR will not alter performance

Footnotes

Uh oh!

Uh oh!

sylvestre commented Apr 28, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

mmastrac commented Apr 17, 2026 •

edited

Loading

codecov-commenter commented Apr 23, 2026 •

edited

Loading

codspeed-hq Bot commented Apr 24, 2026 •

edited

Loading