fix: never panic during diagnostic emission by IWANABETHATGUY · Pull Request #9091 · rolldown/rolldown

IWANABETHATGUY · 2026-04-13T10:46:45Z

Summary

Rolldown should never panic while emitting diagnostics. From a user DX perspective, a bundler crash during warning/error reporting is far worse than a degraded diagnostic — users should always see a meaningful message, even when internal state is inconsistent (e.g. an out-of-range span).

Replace unreachable!() in is_context_too_long with a fallback that renders the label as plain text when the span exceeds source bounds (direct fix for Panic: internal error: entered unreachable code: Diagnostic span is out of range (COMMONJS_VARIABLE_IN_ESM) #9073)
Make Diagnostic::convert_to_string panic-free by gracefully handling ariadne render failures and using from_utf8_lossy
Skip OXC error labels whose spans are unrepresentable as u32 rather than panicking or silently attaching bogus ranges

Test plan

cargo test -p rolldown_error passes
cargo clippy -p rolldown_error clean

Closes #9073

IWANABETHATGUY · 2026-04-13T10:46:59Z

fix: never panic during diagnostic emission #9091 👈 (View in Graphite)
main

How to use the Graphite Merge Queue

Add the label graphite: merge-when-ready to this PR to add it to the merge queue.

You must have a Graphite account in order to use the merge queue. Sign up using this link.

_{An organization admin has enabled the Graphite Merge Queue in this repository.} _{Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.}

This stack of pull requests is managed by Graphite. Learn more about stacking.

netlify · 2026-04-13T10:47:03Z

✅ Deploy Preview for rolldown-rs canceled.

Name	Link
🔨 Latest commit	`e3ed9f5`
🔍 Latest deploy log	https://app.netlify.com/projects/rolldown-rs/deploys/69df20f96ade960008a5de1c

pkg-pr-new · 2026-04-13T11:32:31Z

Open in StackBlitz

@rolldown/browser

npm i https://pkg.pr.new/@rolldown/browser@9091

@rolldown/debug

npm i https://pkg.pr.new/@rolldown/debug@9091

@rolldown/pluginutils

npm i https://pkg.pr.new/@rolldown/pluginutils@9091

rolldown

npm i https://pkg.pr.new/rolldown@9091

@rolldown/binding-android-arm64

npm i https://pkg.pr.new/@rolldown/binding-android-arm64@9091

@rolldown/binding-darwin-arm64

npm i https://pkg.pr.new/@rolldown/binding-darwin-arm64@9091

@rolldown/binding-darwin-x64

npm i https://pkg.pr.new/@rolldown/binding-darwin-x64@9091

@rolldown/binding-freebsd-x64

npm i https://pkg.pr.new/@rolldown/binding-freebsd-x64@9091

@rolldown/binding-linux-arm-gnueabihf

npm i https://pkg.pr.new/@rolldown/binding-linux-arm-gnueabihf@9091

@rolldown/binding-linux-arm64-gnu

npm i https://pkg.pr.new/@rolldown/binding-linux-arm64-gnu@9091

@rolldown/binding-linux-arm64-musl

npm i https://pkg.pr.new/@rolldown/binding-linux-arm64-musl@9091

@rolldown/binding-linux-ppc64-gnu

npm i https://pkg.pr.new/@rolldown/binding-linux-ppc64-gnu@9091

@rolldown/binding-linux-s390x-gnu

npm i https://pkg.pr.new/@rolldown/binding-linux-s390x-gnu@9091

@rolldown/binding-linux-x64-gnu

npm i https://pkg.pr.new/@rolldown/binding-linux-x64-gnu@9091

@rolldown/binding-linux-x64-musl

npm i https://pkg.pr.new/@rolldown/binding-linux-x64-musl@9091

@rolldown/binding-openharmony-arm64

npm i https://pkg.pr.new/@rolldown/binding-openharmony-arm64@9091

@rolldown/binding-wasm32-wasi

npm i https://pkg.pr.new/@rolldown/binding-wasm32-wasi@9091

@rolldown/binding-win32-arm64-msvc

npm i https://pkg.pr.new/@rolldown/binding-win32-arm64-msvc@9091

@rolldown/binding-win32-x64-msvc

npm i https://pkg.pr.new/@rolldown/binding-win32-x64-msvc@9091

commit: d57d799

codspeed-hq · 2026-04-15T02:32:38Z

Merging this PR will not alter performance

✅ 4 untouched benchmarks
⏩ 10 skipped benchmarks¹

_{Comparing 04-13-fix_9073 (83f7c4c) with main (b3b112b)}

10 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. ↩

IWANABETHATGUY · 2026-04-15T05:22:17Z

Merge activity

Apr 15, 5:22 AM UTC: The merge label 'graphite: merge-when-ready' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
Apr 15, 5:22 AM UTC: IWANABETHATGUY added this pull request to the Graphite merge queue.
Apr 15, 5:28 AM UTC: Merged by the Graphite merge queue.

## Summary Rolldown should never panic while emitting diagnostics. From a user DX perspective, a bundler crash during warning/error reporting is far worse than a degraded diagnostic — users should always see a meaningful message, even when internal state is inconsistent (e.g. an out-of-range span). - Replace `unreachable!()` in `is_context_too_long` with a fallback that renders the label as plain text when the span exceeds source bounds (direct fix for #9073) - Make `Diagnostic::convert_to_string` panic-free by gracefully handling ariadne render failures and using `from_utf8_lossy` - Skip OXC error labels whose spans are unrepresentable as `u32` rather than panicking or silently attaching bogus ranges ## Test plan - [x] `cargo test -p rolldown_error` passes - [x] `cargo clippy -p rolldown_error` clean Closes #9073

@Dunqing

## [1.0.0-rc.16] - 2026-04-16 ### 🚀 Features - const enum cross-module inlining support (#8796) by @Dunqing - implement module tagging system for code splitting (#9045) by @hyf0 ### 🐛 Bug Fixes - rolldown_plugin_vite_manifest: handle duplicate chunk names for CSS entries (#9059) by @sapphi-red - improve error message for invalid return values in function options (#9125) by @shulaoda - await async export-star init wrappers (#9101) by @thezzisu - never panic during diagnostic emission (#9091) by @IWANABETHATGUY - include array rest pattern in binding_identifiers (#9112) by @IWANABETHATGUY - rolldown: set worker thread count with ROLLDOWN_WORKER_THREADS (#9086) by @fpotter - rolldown_plugin_lazy_compilation: escape request ID in proxy modules (#9102) by @h-a-n-a - treat namespace member access as side-effect-free (#9099) by @IWANABETHATGUY - relax overly conservative side-effect leak check in chunk optimizer (#9085) by @IWANABETHATGUY - runtime: release `cb` reference after `__commonJS` factory initialization (#9067) by @hyf0-agent - `@__NO_SIDE_EFFECTS__` wrapper should not remove dynamic imports (#9075) by @IWANABETHATGUY - rolldown_plugin_vite_import_glob: use POSIX path join/normalize for glob resolution (#9077) by @shulaoda - emit REQUIRE_TLA error when require() loads a module with top-level await (#9071) by @jaehafe - emit namespace declaration for empty modules in manual chunks (#8993) by @privatenumber - rolldown_plugin_vite_import_glob: keep common base on path segment boundary (#9070) by @shulaoda - prevent circular runtime helper imports during facade elimination (#8989) (#9057) by @IWANABETHATGUY - correct circular dependency check in facade elimination (#9047) by @h-a-n-a - docs: correct dead link in CodeSplittingGroup.tags JSDoc (#9051) by @hyf0 - emit DUPLICATE_SHEBANG warning when banner contains shebang (#9026) by @IWANABETHATGUY ### 🚜 Refactor - use semantic reference flags for member write detection (#9060) by @Dunqing - extract UsedSymbolRefs newtype wrapper (#9130) by @IWANABETHATGUY - dedupe await wrapping in export-star init emit (#9119) by @IWANABETHATGUY - calculate side-effect-free function symbols on demand (#9120) by @IWANABETHATGUY - extract duplicated top-level await handling into shared helper (#9087) by @IWANABETHATGUY - rolldown_plugin_vite_import_glob: use split_first for get_common_base (#9069) by @shulaoda - simplify ESM init deduplication with idiomatic insert check (#9044) by @IWANABETHATGUY ### 📚 Documentation - document runtime module placement strategy in code-splitting design (#9062) by @IWANABETHATGUY - clarify `options` hook behavior difference with Rollup in watch mode (#9053) by @sapphi-red - meta/design: introduce module tags (#9017) by @hyf0 ### ⚡ Performance - convert `generate_transitive_esm_init` to iterative (#9046) by @IWANABETHATGUY ### 🧪 Testing - merge strict/non_strict test variants using configVariants (#9089) by @IWANABETHATGUY ### ⚙️ Miscellaneous Tasks - disable Renovate auto-updates for oxc packages (#9129) by @IWANABETHATGUY - upgrade oxc@0.126.0 (#9127) by @Dunqing - deps: update napi to v3.8.5 (#9126) by @renovate[bot] - deps: update dependency @napi-rs/cli to v3.6.2 (#9123) by @renovate[bot] - move lazy-compilation design doc (#9117) by @h-a-n-a - deps: update dependency vite-plus to v0.1.18 (#9118) by @renovate[bot] - deps: update dependency vite-plus to v0.1.17 (#9113) by @renovate[bot] - deps: update oxc to v0.125.0 (#9094) by @renovate[bot] - deps: update dependency follow-redirects to v1.16.0 [security] (#9103) by @renovate[bot] - deps: update test262 submodule for tests (#9097) by @sapphi-red - deps: update crate-ci/typos action to v1.45.1 (#9096) by @renovate[bot] - deps: update rust crates (#9081) by @renovate[bot] - deps: update npm packages (#9080) by @renovate[bot] - remove outdated TODO in determine_module_exports_kind (#9072) by @jaehafe - rust/test: support `extendedTests: false` shorthand in test config (#9050) by @hyf0 - ci: extract shared infra-changes anchor in path filters (#9054) by @hyf0 - add docs build check to catch dead links in PRs (#9052) by @hyf0 ### ❤️ New Contributors * @thezzisu made their first contribution in [#9101](#9101) * @fpotter made their first contribution in [#9086](#9086) * @jaehafe made their first contribution in [#9071](#9071) * @privatenumber made their first contribution in [#8993](#8993) Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>

github-actions Bot assigned IWANABETHATGUY Apr 13, 2026

IWANABETHATGUY force-pushed the 04-13-fix_9073 branch from b4af2be to d57d799 Compare April 13, 2026 11:15

IWANABETHATGUY added the trigger: preview label Apr 13, 2026

IWANABETHATGUY changed the title ~~fix: 9073~~ fix: never panic during diagnostic emission Apr 13, 2026

IWANABETHATGUY mentioned this pull request Apr 13, 2026

Panic: internal error: entered unreachable code: Diagnostic span is out of range (COMMONJS_VARIABLE_IN_ESM) #9073

Closed

IWANABETHATGUY marked this pull request as ready for review April 15, 2026 02:26

IWANABETHATGUY force-pushed the 04-13-fix_9073 branch from d57d799 to 83f7c4c Compare April 15, 2026 02:26

IWANABETHATGUY requested review from h-a-n-a, hyf0 and shulaoda April 15, 2026 02:27

h-a-n-a approved these changes Apr 15, 2026

View reviewed changes

IWANABETHATGUY added the graphite: merge-when-ready label Apr 15, 2026

graphite-app Bot force-pushed the 04-13-fix_9073 branch from 83f7c4c to e3ed9f5 Compare April 15, 2026 05:24

graphite-app Bot merged commit e3ed9f5 into main Apr 15, 2026
32 checks passed

graphite-app Bot removed the graphite: merge-when-ready label Apr 15, 2026

graphite-app Bot deleted the 04-13-fix_9073 branch April 15, 2026 05:28

github-actions Bot mentioned this pull request Apr 16, 2026

release: v1.0.0-rc.16 #9131

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

fix: never panic during diagnostic emission#9091

fix: never panic during diagnostic emission#9091
graphite-app[bot] merged 1 commit intomainfrom
04-13-fix_9073

IWANABETHATGUY commented Apr 13, 2026 •

edited

Loading

Uh oh!

IWANABETHATGUY commented Apr 13, 2026

Uh oh!

netlify Bot commented Apr 13, 2026 •

edited

Loading

Uh oh!

pkg-pr-new Bot commented Apr 13, 2026

Uh oh!

codspeed-hq Bot commented Apr 15, 2026

Uh oh!

IWANABETHATGUY commented Apr 15, 2026 •

edited by graphite-app Bot

Loading

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Conversation

IWANABETHATGUY commented Apr 13, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Test plan

Uh oh!

IWANABETHATGUY commented Apr 13, 2026

How to use the Graphite Merge Queue

Uh oh!

netlify Bot commented Apr 13, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

✅ Deploy Preview for rolldown-rs canceled.

Uh oh!

pkg-pr-new Bot commented Apr 13, 2026

Uh oh!

codspeed-hq Bot commented Apr 15, 2026

Merging this PR will not alter performance

Footnotes

Uh oh!

IWANABETHATGUY commented Apr 15, 2026 • edited by graphite-app Bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Merge activity

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

IWANABETHATGUY commented Apr 13, 2026 •

edited

Loading

netlify Bot commented Apr 13, 2026 •

edited

Loading

IWANABETHATGUY commented Apr 15, 2026 •

edited by graphite-app Bot

Loading