<details>
<summary> observed in
https://buildkite.com/bun/bun/builds/22442#annotation-test/js/node/zlib/leak.test.ts
</summary>
```
==5045==ERROR: AddressSanitizer: heap-use-after-free on address 0x5220000243c0 at pc 0x00000dad671b bp 0x14f22d4a4990 sp 0x14f22d4a4988
READ of size 8 at 0x5220000243c0 thread T5 (HeapHelper)
======== Stack trace from GDB for HeapHelper-5045.core: ========
Program terminated with signal SIGABRT, Aborted.
#0 0x000014f2c3672eec in ?? () from /lib/x86_64-linux-gnu/libc.so.6
[Current thread is 1 (Thread 0x14f22d4f46c0 (LWP 5050))]
#0 0x000014f2c3672eec in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x000014f2c3623fb2 in raise () from /lib/x86_64-linux-gnu/libc.so.6
#2 0x000014f2c360e472 in abort () from /lib/x86_64-linux-gnu/libc.so.6
#3 0x000000000e3b2ae2 in uw_init_context_1[cold] ()
#4 0x000000000e3b29fc in _Unwind_Backtrace ()
#5 0x00000000046a6bab in __sanitizer::BufferedStackTrace::UnwindSlow(unsigned long, unsigned int) ()
#6 0x00000000046a181d in __sanitizer::BufferedStackTrace::Unwind(unsigned int, unsigned long, unsigned long, void*, unsigned long, unsigned long, bool) ()
#7 0x00000000046885bd in __sanitizer::BufferedStackTrace::UnwindImpl(unsigned long, unsigned long, void*, bool, unsigned int) ()
#8 0x0000000004601127 in __asan::ErrorGeneric::Print() ()
#9 0x0000000004683180 in __asan::ScopedInErrorReport::~ScopedInErrorReport() ()
#10 0x0000000004686567 in __asan::ReportGenericError(unsigned long, unsigned long, unsigned long, unsigned long, bool, unsigned long, unsigned int, bool) ()
#11 0x0000000004686d46 in __asan_report_load8 ()
#12 0x000000000dad671b in ZSTD_sizeof_CCtx (cctx=<optimized out>) at ./build/release-asan/zstd/vendor/zstd/lib/compress/zstd_compress.c:210
#13 0x0000000006d2284d in bun.js.node.zlib.NativeZstd.estimatedSize () at /var/lib/buildkite-agent/builds/ip-172-31-72-121/bun/bun/src/bun.js/node/zlib/NativeZstd.zig:57
#14 ZigGeneratedClasses.JSNativeZstd.JavaScriptCoreBindings.NativeZstd__estimatedSize (thisValue=<optimized out>) at /var/lib/buildkite-agent/builds/ip-172-31-72-121/bun/bun/build/release-asan/codegen/ZigGeneratedClasses.zig:11122
#15 0x000000000852803b in WebCore::JSNativeZstd::visitChildrenImpl<JSC::SlotVisitor> (cell=0x14f22e190840, visitor=...) at ./build/release-asan/./build/release-asan/codegen/ZigGeneratedClasses.cpp:30728
#16 WebCore::JSNativeZstd::visitChildren (cell=0x14f22e190840, visitor=...) at ./build/release-asan/./build/release-asan/codegen/ZigGeneratedClasses.cpp:30734
#17 0x000000000aa99d6c in JSC::MethodTable::visitChildren (this=<optimized out>, cell=<optimized out>, visitor=...) at vendor/WebKit/Source/JavaScriptCore/runtime/ClassInfo.h:115
#18 0x000000000aa99d6c in JSC::SlotVisitor::visitChildren (this=0x14f277028300, cell=0x14f22e190840)
#19 JSC::SlotVisitor::drain(WTF::MonotonicTime)::$_0::operator()(JSC::MarkStackArray&) const (this=<optimized out>, stack=...) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitor.cpp:509
#20 0x000000000aa8f130 in JSC::SlotVisitor::forEachMarkStack<JSC::SlotVisitor::drain(WTF::MonotonicTime)::$_0>(JSC::SlotVisitor::drain(WTF::MonotonicTime)::$_0 const&) (this=0x14f277028300, func=...) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitorInlines.h:193
#21 JSC::SlotVisitor::drain (this=this@entry=0x14f277028300, timeout=<error reading variable: That operation is not available on integers of more than 8 bytes.>, timeout@entry=...) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitor.cpp:499
#22 0x000000000aa90590 in JSC::SlotVisitor::drainFromShared (this=0x14f277028300, sharedDrainMode=JSC::SlotVisitor::HelperDrain, timeout=<error reading variable: That operation is not available on integers of more than 8 bytes.>) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitor.cpp:699
#23 0x000000000aa08726 in JSC::Heap::runBeginPhase(JSC::GCConductor)::$_1::operator()() const (this=<optimized out>) at vendor/WebKit/Source/JavaScriptCore/heap/Heap.cpp:1508
#24 WTF::SharedTaskFunctor<void (), JSC::Heap::runBeginPhase(JSC::GCConductor)::$_1>::run() (this=<optimized out>) at .WTF/Headers/wtf/SharedTask.h:91
#25 0x000000000aa3b596 in WTF::ParallelHelperClient::runTask(WTF::RefPtr<WTF::SharedTask<void ()>, WTF::RawPtrTraits<WTF::SharedTask<void ()> >, WTF::DefaultRefDerefTraits<WTF::SharedTask<void ()> > > const&) (this=0x14f22e000428, task=...) at vendor/WebKit/Source/WTF/wtf/ParallelHelperPool.cpp:110
#26 0x000000000aa3d976 in WTF::ParallelHelperPool::Thread::work (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/ParallelHelperPool.cpp:201
#27 0x000000000aa4210d in WTF::AutomaticThread::start(WTF::AbstractLocker const&)::$_0::operator()() const (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/AutomaticThread.cpp:225
#28 WTF::Detail::CallableWrapper<WTF::AutomaticThread::start(WTF::AbstractLocker const&)::$_0, void>::call() (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/Function.h:53
#29 0x0000000008958ada in WTF::Function<void ()>::operator()() const (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/Function.h:82
#30 WTF::Thread::entryPoint (newThreadContext=<optimized out>) at vendor/WebKit/Source/WTF/wtf/Threading.cpp:272
#31 0x0000000008a65689 in WTF::wtfThreadEntryPoint (context=0x13b5) at vendor/WebKit/Source/WTF/wtf/posix/ThreadingPOSIX.cpp:255
#32 0x000000000467d347 in asan_thread_start(void*) ()
#33 0x000014f2c36711f5 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#34 0x000014f2c36f189c in ?? () from /lib/x86_64-linux-gnu/libc.so.6
```
</details>
`ZSTD_sizeof_CCtx` and `ZSTD_sizeof_DCtx` can not be relied upon to be
thread-safe and estimatedSize may be called from any thread
### What does this PR do?
After 10s of inactivity in the thread pool, this releases memory more
aggressively back to the operating system
### How did you verify your code works?
### What does this PR do?
Fixes a crash related to pipelines
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
## Summary
Fixes a bug in napi_get_value_bigint_words where the function would
return the number of words copied instead of the actual word count
needed when the provided buffer is smaller than required.
## The Problem
When napi_get_value_bigint_words was called with a buffer smaller than
the actual BigInt size, it would incorrectly return the buffer size
instead of the actual word count needed. This doesn't match Node.js
behavior.
### Example
BigInt that requires 2 words: 0x123456789ABCDEF0123456789ABCDEFn
Call with buffer for only 1 word
- Before fix: word_count = 1 (buffer size)
- After fix: word_count = 2 (actual words needed)
## The Fix
Changed napi_get_value_bigint_words to always set word_count to the
actual number of words in the BigInt, regardless of buffer size.
## Test Plan
- Added test test_bigint_word_count that verifies the word count is
correctly returned
- Added test test_ref_unref_underflow for the existing
napi_reference_unref underflow protection
- Both tests pass with the fix and match Node.js behavior
🤖 Generated with [Claude Code](https://claude.ai/code)
---------
Co-authored-by: Claude <noreply@anthropic.com>
### What does this PR do?
This PR adds lldb pretty printing support for `bun.String`, `ZigString`
and `WTFStringImpl` so you don't have to click through so many fields to
what the actual string value is.
### What does this PR do?
Removes the unused `capturedError` fixing the oxlint error. This
variable is never assigned to, hence the block on L1094 can never run.
### How did you verify your code works?
Existing tests
### What does this PR do?
It is easy to confuse `lines` and `columns` fields in `LineColumnOffset`
struct inside of `src/sourcemap/sourcemap.zig` as being either one or
zero based. The sourcemap spec says line and column offsets are zero
based. There was a place that was incorrectly assuming it was one based.
This PR switches it to use `bun.Ordinal` instead of bare `u32` integers
to prevent bugs and from this happening again.
## Summary
This PR adds a comprehensive TypeScript CLI flag parser that reads the
`--help` menu for every Bun command and generates structured JSON data
for shell completion generators.
### Features
- **🔍 Complete command discovery**: Automatically discovers all 22 Bun
commands
- **📋 Comprehensive flag parsing**: Extracts 388+ flags with
descriptions, types, defaults, and choices
- **🌳 Nested subcommand support**: Handles complex cases like `bun pm
cache rm`, `bun pm pkg set`
- **🔗 Command aliases**: Supports `bun i` = `bun install`, `bun a` =
`bun add`, etc.
- **🎯 Dynamic completions**: Integrates with `bun getcompletes` for
scripts, packages, files, binaries
- **📂 File type awareness**: Knows when to complete `.js/.ts` files vs
test files vs packages
- **⚡ Special case handling**: Handles bare `bun` vs `bun run` and other
edge cases
### Generated Output
The script generates `completions/bun-cli.json` with:
- 21 commands with full metadata
- 47 global flags
- 16 pm subcommands (including nested ones)
- 54+ examples
- Dynamic completion hints
- Integration info for existing shell completions
### Usage
```bash
bun run scripts/generate-cli-completions.ts
```
Output saved to `completions/bun-cli.json` for use by future shell
completion generators.
### Perfect Shell Completions Ready
This JSON structure provides everything needed to generate perfect shell
completions for fish, bash, and zsh with full feature parity to the
existing hand-crafted completions. It captures all the complex cases
that make Bun's CLI completions work seamlessly.
The generated data structure includes:
- Context-aware flag suggestions
- Proper file type filtering
- Package name completions
- Script and binary discovery
- Subcommand nesting
- Alias handling
- Dynamic completion integration
🤖 Generated with [Claude Code](https://claude.ai/code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: graphite-app[bot] <96075541+graphite-app[bot]@users.noreply.github.com>
### What does this PR do?
The `then` function in `transpiler.transform` can cause GC, which means
it can cause the `Transpiler` to become freed, which means that if that
same transpiler is in use by another run on the other thread, it could
have pointers to invalid memory.
Also, `ESMCondition` has unnecesasry memory allocations and there is a
very tiny memory leak in optionsFromLoaders
### How did you verify your code works?
Existing tests
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
Removes `DevServer.relative_path_buf` field and replaces it with usages
of `bun.path_buffer_pool` which is better than this debug lock thing
going on
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Splits up js_parser.zig into multiple files. Also changes visitExprInOut
to use function calls rather than switch
Not ready:
- [ ] P.zig is ~70,000 tokens, still needs to get smaller
- [x] ~~measure zig build time before & after (is it slower?)~~ no
significant impact
---------
Co-authored-by: pfgithub <6010774+pfgithub@users.noreply.github.com>
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Fixes#21189
`.pause()` should unref but it should still continue to emit `readable`
events (although it should not send `data` events)
also stdin.unref() should not pause input, it should only prevent stdin
from keeping the process alive.
DRAFT:
- [x] ~~this causes a bug where `process.stdin.on("readable", () => {});
process.stdin.pause()` will allow the process to exit when it
shouldn't.~~ fixed
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
We should not call .deinit() after .toJS otherwise hasPendingActivity
will access invalid memory
### How did you verify your code works?
Test run it with debug build on macos or asan on and will catch it
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
The DevSever's `IncrementalGraph` uses a data-oriented design memory
management style, storing data in lists and using indices instead of
pointers.
In conventional memory management, when we free a pointer and
accidentally use it will trip up asan. Obviously this doesn't apply when
using lists and indices, so this PR adds a check in debug & asan builds.
Everytime we free an `Edge` we better make sure that there are no more
dangling references to that spot.
This caught a case where we weren't setting `g.first_import[file_index]
= .none` when deleting a file's imports, causing a dangling reference
and out of bounds access.
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
dropAllLocks causes Thread::yield several times which means more system
calls which means more thread switches which means slower
### How did you verify your code works?
### What does this PR do?
Releasing heap access causes all the heap helper threads to wake up and
lock and then unlock futexes, but it's important to do that to ensure
finalizers run quickly.
That means releasing heap access is a balance between:
1. CPU usage
2. Memory usage
Not releasing heap access causes benchmarks like
https://github.com/oven-sh/bun/pull/14885 to regress due to finalizers
not being called quickly enough.
Releasing heap access too often causes high idle CPU usage.
For the following code:
```
setTimeout(() => {}, 10 * 1000)
```
command time -v when with defaultRemainingRunsUntilSkipReleaseAccess =
0:
>
> Involuntary context switches: 605
>
command time -v when with defaultRemainingRunsUntilSkipReleaseAccess =
5:
>
> Involuntary context switches: 350
>
command time -v when with defaultRemainingRunsUntilSkipReleaseAccess =
10:
>
> Involuntary context switches: 241
>
Also comapre the #14885 benchmark with different values.
The idea here is if you entered JS "recently", running any
finalizers that might've been waiting to be run is a good idea.
But if you haven't, like if the process is just waiting on I/O
then don't bother.
### How did you verify your code works?
### What does this PR do?
Instead of holding a strong for the options object passed with the
handlers, we make each of the callbacks kept alive by the handlers and
it detaches once the detachFromJS function is called.
This should fix#21570, which looks like it was caused by wrapper
functions for AsyncLocalStorage getting collected prematurely.
fixes#21254fixes#21553fixes#21422
### How did you verify your code works?
Ran test/js/node/http2/node-http2.test.js