fix(watch): filter out Access events to prevent infinite rebuild loop on Linux by hyf0-agent · Pull Request #8557 · rolldown/rolldown

hyf0-agent · 2026-03-05T16:53:05Z

Summary

Fix infinite rebuild loop in watch mode on Linux (regression in rc.7).

Root Cause

rolldown-notify with TargetMode::TrackPath registers inotify watches including IN_OPEN and IN_ATTRIB flags. When the build process reads watched source files during bundling, inotify emits Access events (EventKind::Access(Open), Access(Read), Access(Close)).

The previous catch-all _ => WatcherChangeKind::Update in TaskFsEventHandler::map_event_kind mapped these Access events to file-change notifications, causing:

build reads src/main.js → inotify fires IN_OPEN
→ notify emits Access(Open) → map_event_kind returns Update
→ watcher triggers rebuild → build reads src/main.js again → ∞

Evidence from strace:

inotify_add_watch(21, ".../src", IN_MODIFY|IN_ATTRIB|IN_CLOSE_WRITE|IN_OPEN|IN_MOVED_FROM|IN_MOVED_TO|IN_CREATE|IN_DELETE)

Evidence from inotifywait — the only events on source files during each rebuild cycle are reads:

OPEN src/main.js → ACCESS → CLOSE_NOWRITE
OPEN src/hello.js → ACCESS → CLOSE_NOWRITE

Fix

Only map Create, Remove, and Modify events to rebuild triggers. All other event kinds (Access, Other, Any) return None and are filtered out before reaching the coordinator.

Test Plan

Reproduced on Linux (Ubuntu, kernel 6.14.0) with a minimal project:

Before fix: editing any source file triggers infinite rebuild loop (~2-3ms per cycle)
After fix: single rebuild on file change, watcher stabilizes correctly

… on Linux On Linux, `rolldown-notify` with `TargetMode::TrackPath` registers inotify watches that include `IN_OPEN` and `IN_ATTRIB` flags. When the build process reads watched source files, these flags cause inotify to emit Access events. The previous catch-all `_ => WatcherChangeKind::Update` mapped these Access events to file-change notifications, causing: build reads src → inotify fires IN_OPEN → watcher treats as Update → triggers rebuild → build reads src again → infinite loop Fix: only map Create, Remove, and Modify events to rebuild triggers. All other event kinds (Access, Other, Any) are now ignored. Closes rolldown#8555

pkg-pr-new · 2026-03-06T02:30:52Z

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commit: c73f601

sapphi-red

The code looks good to me.
I guess we should align with

rolldown/crates/rolldown_dev/src/bundle_coordinator.rs

Lines 152 to 175 in 1b0ff2d

    
           EventKind::Create(_create_kind) => { 
        
             for path in batched_event.detail.paths { 
        
               changed_files.insert(path, WatcherChangeKind::Create); 
        
             } 
        
           } 
        
           #[cfg(target_os = "macos")] 
        
           EventKind::Modify(notify::event::ModifyKind::Metadata(_)) 
        
             if !self.ctx.options.use_polling => 
        
           { 
        
             // When using kqueue on mac, ignore metadata changes as it happens frequently and doesn't affect the build in most cases 
        
             // Note that when using polling, we shouldn't ignore metadata changes as the polling watcher prefer to emit them over 
        
             // content change events 
        
           } 
        
           EventKind::Modify(notify::event::ModifyKind::Name(notify::event::RenameMode::From)) 
        
           | EventKind::Remove(_) => { 
        
             for path in batched_event.detail.paths { 
        
               changed_files.insert(path, WatcherChangeKind::Delete); 
        
             } 
        
           } 
        
           EventKind::Modify(_modify_kind) => { 
        
             for path in batched_event.detail.paths { 
        
               changed_files.insert(path, WatcherChangeKind::Update); 
        
             } 
        
           }

later

Treat Modify(Name(RenameMode::From)) as Delete to match the event handling in BundleCoordinator::handle_watch_event, where a rename-from is treated as a file deletion. Ref: rolldown#8557 (review)

@hyf0

## [1.0.0-rc.8] - 2026-03-09 ### 🚀 Features - watch: enable full functional fs watcher in wasm (#8575) by @hyf0 - watch: expose debounce related options (#8572) by @hyf0 ### 🐛 Bug Fixes - detect new URL(…, import.meta.url) with no-sub template literal (#8565) by @char - devtools: trace dynamic imports in devtools (#8581) by @cal-gooo - watch: rebuild when a previously missing file is created (#8562) by @hyf0-agent - watch: filter out Access events to prevent infinite rebuild loop on Linux (#8557) by @hyf0-agent ### 🚜 Refactor - watch: remove auto watch for fail imports (#8585) by @hyf0 - fs_watcher: unify the way of constructing watcher (#8571) by @hyf0 - cli: migrate CLI to CAC (#8551) by @h-a-n-a - switch asset module support from hard-code to builtin plugin (#8546) by @hyf0 ### 📚 Documentation - fix subject-verb agreement in why-bundlers.md (#8591) by @brandonzylstra - maintenance: align release and canary workflow guide (#8538) by @minsoo-web - add `format` option to directives example config (#8590) by @shulaoda - fix: change twitter to x logo in team (#8552) by @mdong1909 - correct composable filter support explanation (#8550) by @sapphi-red ### ⚡ Performance - testing: share tokio runtime across fixture tests (#8567) by @Boshen ### 🧪 Testing - hmr: fix infinite loop in dev server test retry logic (#8576) by @hyf0-agent - cli: add more cli-e2e test cases (#8548) by @h-a-n-a ### ⚙️ Miscellaneous Tasks - docs: update in-depth/directives for `output.strict` option (#8535) by @minsoo-web - add PNPM_HOME Dev Drive mapping to Windows CI workflows (#8589) by @Boshen - deps: update github-actions (#8588) by @renovate[bot] - move Windows cargo target dir to Dev Drive (#8586) by @Boshen - optimize cache keys to fix race conditions and reduce usage (#8578) by @Boshen - remove WASI build & test pipeline (#8580) by @Boshen - remove unnecessary submodule checkouts (#8577) by @Boshen - use Dev Drive for Windows CI jobs (#8574) by @Boshen - skip redundant native binding build for browser and remove standalone job (#8573) by @Boshen - parallelize Node tests on ubuntu, single Node 24 on macOS/windows (#8570) by @Boshen - docs: bump @voidzero-dev/vitepress-theme to 4.8.0 (#8558) by @crusty-voidzero - dedupe type-check from dev server workflow (#8554) by @Boshen ### ❤️ New Contributors * @brandonzylstra made their first contribution in [#8591](#8591) * @char made their first contribution in [#8565](#8565) * @cal-gooo made their first contribution in [#8581](#8581) * @hyf0-agent made their first contribution in [#8562](#8562) * @h-a-n-a made their first contribution in [#8551](#8551) Co-authored-by: shulaoda <[email protected]>

hyf0 requested review from sapphi-red and shulaoda March 5, 2026 16:56

hyf0-agent added 2 commits March 6, 2026 01:11

chore: trigger CI

2d44b6d

chore: retrigger CI

02c2d07

hyf0 added the trigger: preview label Mar 6, 2026

sapphi-red approved these changes Mar 6, 2026

View reviewed changes

refactor: align event mapping with BundleCoordinator

a58608b

Treat Modify(Name(RenameMode::From)) as Delete to match the event handling in BundleCoordinator::handle_watch_event, where a rename-from is treated as a file deletion. Ref: rolldown#8557 (review)

hyf0 merged commit b613c7d into rolldown:main Mar 6, 2026
31 checks passed

sapphi-red mentioned this pull request Mar 6, 2026

Many packages are not published when publishing multiple packages stackblitz-labs/pkg.pr.new#479

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github-actions bot mentioned this pull request Mar 9, 2026

release: v1.0.0-rc.8 #8592

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fix(watch): filter out Access events to prevent infinite rebuild loop on Linux#8557

fix(watch): filter out Access events to prevent infinite rebuild loop on Linux#8557
hyf0 merged 4 commits intorolldown:mainfrom
hyf0-agent:fix/watch-infinite-rebuild-linux

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	EventKind::Create(_create_kind) => {
	for path in batched_event.detail.paths {
	changed_files.insert(path, WatcherChangeKind::Create);
	}
	}
	#[cfg(target_os = "macos")]
	EventKind::Modify(notify::event::ModifyKind::Metadata(_))
	if !self.ctx.options.use_polling =>
	{
	// When using kqueue on mac, ignore metadata changes as it happens frequently and doesn't affect the build in most cases
	// Note that when using polling, we shouldn't ignore metadata changes as the polling watcher prefer to emit them over
	// content change events
	}
	EventKind::Modify(notify::event::ModifyKind::Name(notify::event::RenameMode::From))
	\| EventKind::Remove(_) => {
	for path in batched_event.detail.paths {
	changed_files.insert(path, WatcherChangeKind::Delete);
	}
	}
	EventKind::Modify(_modify_kind) => {
	for path in batched_event.detail.paths {
	changed_files.insert(path, WatcherChangeKind::Update);
	}
	}

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hyf0-agent commented Mar 5, 2026

Summary

Root Cause

Fix

Test Plan

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