Upgrade WebKit to ea1bfb85d259 by robobun · Pull Request #26161 · oven-sh/bun

robobun · 2026-01-16T08:20:20Z

Summary

Upgrades WebKit from c4d4cae03ece to ea1bfb85d259
Merges upstream WebKit changes into oven-sh/webkit fork

WebKit Upgrade Summary (JavaScriptCore Changes)

JSType Enum Changes

No breaking changes to JSType enum from upstream. The diff showing InternalFieldTupleType removal is actually showing Bun's custom addition - upstream WebKit does not have this type. The Bun fork maintains InternalFieldTupleType after DerivedStringObjectType, which is preserved during the upgrade.

Notable Performance Improvements

ARM64 Conditional Compare Chain (ccmp/ccmn)

Commit: 2cd6a734ed6c
Implements ARM64 ccmp/ccmn instruction chaining for compound boolean expressions
Converts patterns like if (x0 == 0 && x1 == 1) into efficient conditional compare sequences
Reduces branch prediction misses and code size
Introduces new Air opcodes: CompareOnFlags, CompareConditionallyOnFlags, BranchOnFlags

Extended Constant Materialization for Float16/Float/Double/V128

Commit: 0521cc7f331a
Enhanced ARM64 constant materialization using movi, mvni, and vector fmov
Avoids memory loads for Float constants (32-bit values can now be materialized directly)
Adds FPImm128 and Move128ToVector Air instructions

DFG/FTL Storage Pointer Improvements

Commits: 00c0add58ec3, 7051d3ac1f34
FTL Phis now properly support storage (butterfly) pointers
Introduces KnownStorageUse for all storage operands in DFG/FTL
Fixes issues with Array allocation sinking when creating storage Phis
Improves GC safety by ensuring butterfly pointers are properly tracked

Bug Fixes

Thread Termination Race Condition

Commit: 23922a766f07
Fixes race condition in VM::m_hasTerminationRequest between main thread and worker threads
Moves setHasTerminationRequest() call into VMTraps::handleTraps() to eliminate race

ThrowScope Exception Clearing

Commit: 67abaaa35c4d
ThrowScopes can no longer accidentally clear termination exceptions
Introduces tryClearException() which fails on termination exceptions
Affects iterator operations, promises, and WebCore stream handling

Bytecode Cache JIT Threshold

Commit: e0644034f46e
Functions loaded from bytecode cache now correctly set JIT threshold
Previously, cached functions would JIT immediately on first execution

Wasm Fixes

Commit: 8579516f4b61 - Fix JIT-less Wasm-to-JS i31ref marshalling for i31 values in double format
Commit: 22b6a610f6ff - Fix nullability for wasm js-string builtins return types (cast, fromCharCode, fromCodePoint, concat, substring)
Commit: 5ad2efd177db - Optimize Wasm BlockSignature to avoid lock contention during parsing

32-bit ARM (Armv7) Fix

Commit: 9cc23c0e75b7
Fixes tail call shuffler register allocation on 32-bit ARM
Prevents assertion failures when JSValue can load via FPR but GPRs are exhausted

New Features

Temporal PlainYearMonth Support

Commit: d865004780e6
Enables all PlainYearMonth test262 tests
Fixes several bugs in month code handling and rounding modes

Wasm IPInt Execution Tracing

Commit: 634156af4114
Adds --traceWasmIPIntExecution option for debugging WebAssembly interpreter execution

Code Quality Improvements

Commit: 31bc5e6778d4 - JSRegExpStringIterator reduced from 56 to 40 bytes by merging boolean fields into bitfield
Commit: cda948675446 - Fix fragile include dependency in JSC::getCallDataInline
Commit: bd87f5db107e - Fix unretained local variable warnings in JavaScriptCore/API

Merge Conflicts Resolved

Fixed 4 merge conflicts related to Bun-specific patches:

Source/JavaScriptCore/API/JSVirtualMachine.mm - Removed JSLockHolder as per Bun's patch
Source/JavaScriptCore/runtime/JSBoundFunction.h - Used relative includes instead of framework includes
Source/JavaScriptCore/runtime/JSObjectInlines.h - Used relative includes and updated JSFunction.h to JSFunctionInlines.h
Source/WTF/wtf/text/WTFString.h - Preserved ExternalStringImpl support

Test plan

WebKit builds successfully (bun build.ts debug)
JSType enum values verified to be compatible
CI builds and tests pass

🤖 Generated with Claude Code

Updates WebKit from c4d4cae03ece to ea1bfb85d259. Notable JSC changes: - ARM64 ccmp/ccmn instruction chaining for better branch prediction - Extended constant materialization for Float16/Float/Double/V128 - DFG/FTL storage pointer improvements - Thread termination race condition fix - ThrowScope exception clearing changes (tryClearException replaces clearException) - Various Wasm and Temporal fixes Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

robobun · 2026-01-16T08:20:31Z

^{Updated 7:03 PM PT - Jan 16th, 2026}

❌ Your commit 0cbfc4ed has 2 failures in Build #35093 (All Failures):

test/integration/next-pages/test/dev-server.test.ts - 1 failing on 🍎 13 aarch64
test/js/node/worker_threads/worker_threads.test.ts - pid 6263 segmentation fault on 🐧 13 x64-baseline

🧪 To try this PR locally:

bunx bun-pr 26161

That installs a local version of the PR into your bun-26161 executable, so you can run:

bun-26161 --bun

coderabbitai · 2026-01-16T08:22:12Z

Walkthrough

This PR changes many exception-clearing calls from clearException() to tryClearException() (discarding return values), updates the default WEBKIT_VERSION in the CMake script, fixes UTF‑8 lifetime issues in timer/codegen code, and updates the CLEAR_IF_EXCEPTION macro to use tryClearException().

Changes

Cohort / File(s)	Summary
WebKit version update `cmake/tools/SetupWebKit.cmake`	Updated default `WEBKIT_VERSION` from `c4d4cae03ecef2791f7ad5dd795f722d8be87d41` to `5ae5f07f29059c183a8db2eef2c9aabd474ec73c`
Exception handling macro `src/bun.js/bindings/headers-handwritten.h`	`CLEAR_IF_EXCEPTION(scope__)` changed from `scope__.clearException();` to `(void)scope__.tryClearException();`
Bindings-wide exception migration `src/bun.js/bindings/...`, `src/bun.js/bindings/bindings.cpp`	Replaced many `clearException()` calls with `(void)scope.tryClearException()` / `(void)catchScope.tryClearException()` across numerous binding files (BunObject, BunPlugin, BunProcess, CallSite, ErrorCode, ErrorStackTrace, JSCommonJSModule, ModuleLoader, etc.)
WebCore & helper code `src/bun.js/bindings/helpers.h`, `src/bun.js/bindings/webcore/...`	Switched `clearException()` → `(void)tryClearException()` in WebCore integration and helper files (JSCallbackData, JSDOMPromiseDeferred, JSEventListener, SerializedScriptValue, etc.)
Node / module / runtime `src/bun.js/modules/...`, `src/bun.js/bindings/node/...`	Switched exception clears to `tryClearException()` in module and Node-related files (NodeModuleModule, NodeProcessModule, ObjectModule, NodeTimers, NodeTimerObject, NodeVM*, NodeVMSpecialSandbox change adds proxy revocation check)
Crypto / N-API / WebCrypto / SQLite `src/bun.js/bindings/napi.cpp`, `src/bun.js/bindings/node/crypto/...`, `src/bun.js/bindings/sqlite/JSSQLStatement.cpp`, `src/bun.js/bindings/webcrypto/JSSubtleCrypto.cpp`	Replaced `clearException()` with `(void)tryClearException()`; sqlite changes also adjust UTF‑8/static storage for paths and entry points
UTF‑8 lifetime & codegen fixes `src/bun.js/bindings/node/NodeTimers.cpp`, `src/codegen/generate-classes.ts`	Preserve UTF‑8 view objects to avoid dangling pointers when extracting `const char*` from temporary UTF‑8 views
Misc bindings & modules `src/bun.js/modules/`, `src/bun.js/bindings/`	Multiple small replacements of `scope.clearException()` → `(void)scope.tryClearException()` across additional files (JSMockFunction, JSBundlerPlugin, JSX509Certificate, ZigGlobalObject, etc.)

Possibly related PRs

Enable CHECK_REF_COUNTED_LIFECYCLE in WebKit #25705 — Also updates cmake/tools/SetupWebKit.cmake default WEBKIT_VERSION (same file-level change).
Fix #23865 #24355 — Modifies exception-clearing behavior in src/bun.js/bindings/ZigGlobalObject.cpp (related exception-handling edits).
Fix WriteBarrier initialization to use WriteBarrierEarlyInit #23435 — Changes JSCommonJSModule implementation (overlaps with exception-handling edits in JSCommonJSModule.cpp).

Suggested reviewers

nektro

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Upgrade WebKit to ea1bfb85d259' directly and clearly describes the main change - a WebKit version upgrade with the specific commit hash.
Description check	✅ Passed	The PR description provides comprehensive details about the WebKit upgrade, changes, bug fixes, and merge conflicts resolved. While it exceeds the template's simple format, it contains all necessary information about what the PR does and verification steps.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

- Replace clearException() with tryClearException() for ThrowScope/CatchScope - Fix dangling pointer issues with utf8().data() by keeping CString alive - Update SetupWebKit.cmake to use release 5ae5f07f29059c183a8db2eef2c9aabd474ec73c Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

…ile not found" (#26126) ## Summary - When running `bun <file>` on a file with an unsupported type (e.g., `.css`, `.yaml`, `.toml`), Bun now shows a helpful error message instead of the misleading "File not found" - Tracks when a file is resolved but has a loader that can't be run directly - Shows the actual file path and file type in the error message **Before:** ``` error: File not found "test.css" ``` **After:** ``` error: Cannot run "/path/to/test.css" note: Bun cannot run css files directly ``` ## Test plan - [x] Added regression test in `test/regression/issue/1365.test.ts` - [x] Test verifies unsupported files show "Cannot run" error - [x] Test verifies nonexistent files still show "File not found" - [x] Test fails with `USE_SYSTEM_BUN=1` and passes with debug build Fixes #1365 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Bot <claude-bot@bun.sh> Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com> Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>

…led (#26175) The signature size adjustment was being applied unconditionally, but it should only happen when building for ARM64 and codesigning is enabled. This prevents incorrect offset calculations on non-ARM64 platforms. --------- Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

…ogs (#26177) ## Summary - Fetches complete logs from BuildKite's public API (no token required) - Saves logs to `/tmp/bun-build-{number}-{platform}-{step}.log` - Shows log file path in output for each failed job - Displays brief error summary (unique errors, max 5) - Adds help text with usage examples (`--help`) - Groups failures by type (build/test/other) - Shows annotation counts with link to view full annotations - Documents usage in CLAUDE.md ## Test plan - [x] Tested with build #35051 (9 failed jobs) - [x] Verified logs saved to `/tmp/bun-build-35051-*.log` - [x] Verified error extraction and deduplication works - [x] Verified `--help` flag shows usage 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Bot <claude-bot@bun.sh> Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

…-ea1bfb85d259

The previous code was assigning a pointer to temporary data that would be destroyed at the end of the expression. Use a static CString to keep the string alive for the lifetime of the process. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

The script wasn't recognizing the 'started' build state, which caused it to incorrectly report builds as having no failures when they were still running. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Two fixes for node:vm module after the WebKit upgrade: 1. NodeVMModule.cpp: Use DECLARE_CATCH_SCOPE(vm).clearException() instead of scope.tryClearException() when handling termination exceptions. The tryClearException() method now returns false without clearing termination exceptions, causing assertion failures later. 2. NodeVM.cpp: Add extra safety check for ProxyObject handler value to ensure it's an object before casting with jsCast<JSObject*>. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

github-actions Bot added the claude label Jan 16, 2026

[autofix.ci] apply automated fixes

3ec2839

Claude Bot and others added 9 commits January 16, 2026 22:11

feat(node:inspector): implement Profiler API (#25939)

8cfd824

Merge remote-tracking branch 'origin/main' into claude/webkit-upgrade…

32410c5

…-ea1bfb85d259

fix(scripts): add 'started' state to buildkite-failures.ts

1965dcf

The script wasn't recognizing the 'started' build state, which caused it to incorrectly report builds as having no failures when they were still running. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Jarred-Sumner merged commit b2e5c6c into main Jan 17, 2026
51 of 55 checks passed

Jarred-Sumner deleted the claude/webkit-upgrade-ea1bfb85d259 branch January 17, 2026 02:46

This was referenced Jan 18, 2026

fix(bindings): handle errors from String.toJS() for oversized strings #26213

Merged

Update WebKit #26381

Merged

This was referenced Mar 18, 2026

Crash in Github actions when building basic React project #25803

Closed

Bun segfault during containerd / buildkitd (bun alpine docker image) build of nuxt app #22909

Closed

robobun mentioned this pull request Jul 24, 2026

Bun segmentation fault on oven/bun:alpine docker image (JSC::CheckPrivateBrandStatus::computeFor) #22873

Closed

robobun mentioned this pull request Oct 31, 2026

require(): remove the cache entry of a built-in whose load a node:vm timeout ended #47543

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Upgrade WebKit to ea1bfb85d259 - #26161

Upgrade WebKit to ea1bfb85d259#26161
Jarred-Sumner merged 11 commits into
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claude/webkit-upgrade-ea1bfb85d259

robobun commented Jan 16, 2026

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robobun commented Jan 16, 2026

Summary

WebKit Upgrade Summary (JavaScriptCore Changes)

JSType Enum Changes

Notable Performance Improvements

ARM64 Conditional Compare Chain (ccmp/ccmn)

Extended Constant Materialization for Float16/Float/Double/V128

DFG/FTL Storage Pointer Improvements

Bug Fixes

Thread Termination Race Condition

ThrowScope Exception Clearing

Bytecode Cache JIT Threshold

Wasm Fixes

32-bit ARM (Armv7) Fix

New Features

Temporal PlainYearMonth Support

Wasm IPInt Execution Tracing

Code Quality Improvements

Merge Conflicts Resolved

Test plan

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Walkthrough

Changes

Possibly related PRs

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robobun commented Jan 16, 2026 •

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