v33.0.1: Release Wasmtime 33.0.1 (#11120)

33.0.1

Released 2025-06-24.

Fixed

• Fix a panic with host-defined tables/globals and concrete reference
  types.
  #11103

v32.0.1: Release Wasmtime 32.0.1 (#11118)

32.0.1

Released 2025-06-24.

Fixed

• Fix a panic with host-defined tables/globals and concrete reference
  types.
  #11103

v24.0.3: Release Wasmtime 24.0.3 (#11121)

24.0.3

Released 2025-06-24.

Fixed

• Fix a panic with host-defined tables/globals and concrete reference
  types.
  #11103

v34.0.0: Release Wasmtime 34.0.0 (#11085)

34.0.0

Released 2025-06-20.

Added

• Support for SIMD in the Pulley interpreter can now be disabled at compile-time
  to shrink the size of the final binary.
  #10727

• The C API now has wasmtime_trap_new_code to create a wasm_trap_t from
  its code.
  #10765

• Winch's support for x86_64 is now classified with tier 1 support in Wasmtime.
  #10755

• Winch's support for aarch64 now implements stack checks to pass many more spec
  tests.
  #10763

• Cranelift's s390x backend now has full support for the f128 type.
  #10774

• Wasmtime's C API for the component model has initial support for calling
  functions.
  #10697
  #10841
  #10858
  #10864
  #10877

• The wasmtime wast command now has a --generate-dwarf flag to show
  filename/line number information for backtraces.
  #10780

Changed

• The shape of bindgen!-generated add_to_linker functions has changed with
  the removal of GetHost and replacement of a HasData trait. For more
  information see the associated PR.
  #10770

• Wasmtime's Store<T> now requires that T: 'static. This is done in
  preparation for merging WASIp3 work to the main repository with some more
  information on the associated PR.
  #10760

• The wasmtime::component::Instance::instance_pre method is now public.
  #10761

• Wasmtime and Cranelift's minimnum supported version of Rust (MSRV) is now
  1.85.0.
  #10785

• Cranelift's debugtrap on aarch64 now generates brk #0xf000 for debuggers
  to recognize it.
  #10813

• The wasi-http implementation no longer generates a trap if the handle to
  receive the response on the host is dropped early.
  #10833

• The wasmtime serve command will now send some boilerplate descriptive HTML
  on a 500 server error instead of nothing.
  #10851

• A significant amount of work has gone into the new assembler for the x64
  backend. Too many PRs to list here but progress continues apace at defining
  all machine instructions in a standalone crate.

• Cranelift will now reject unimplemented big-endian loads/stores on backends
  that do not implement this functionality.
  #10863

• The wasmtime explore generated HTML handles large modules better now.
  #10892

• Wasmtime's internal representation of wasmtime::Func has changed and a
  previous optimization of Func::call has been lost. If affected it'd
  recommended to use Func::call_unchecked instead or to open an issue.
  #10897

v33.0.0: Release Wasmtime 33.0.0 (#10812)

33.0.0

Released 2025-05-20.

Added

• Cranelift now has initial support for try_call and try_call_indirect
  instructions, to be used in the future for the WebAssembly exception-handling
  proposal. Wasmtime does not yet implement this proposal yet.
  #10510
  #10557
  #10593

• Cranelift can now optimize some simple possibly-side-effectful instructions,
  such as division.
  #10524

• Wasmtime now supports --invoke for components using the WAVE format.
  #10054

• Initial support for the Component Model has landed in Wasmtime's C API. Note
  that the API is not yet feature-complete, however.
  #10566
  #10598
  #10651
  #10675

• Wasmtime's C++ API is now available from this repository and the
  bytecodealliance/wasmtime-cpp repository has been archived. Additionally the
  monolithic wasmtime.hh header file has been split into separate header
  files.
  #10582
  #10600

• Wasmtime's cookbook-style documentation has been expanded.
  #10630

• Wasmtime's now supports custom yield behavior when using epoch interrupts.
  #10671

Changed

• Wasmtime's bindgen now type-checks export functions in the constructor of
  the generated {Worldname}Pre or {Worldname} structs, rather than at the
  call of the export function.
  #10610

• Wasmtime's component::Component and component::Instance now have consistient
  get_export and get_export_index methods, which return (ComponentItem, ComponentExportIndex) and ComponentExportIndex, respectively.
  #10597

• On failure, wasmtime serve gives an internal server error response, rather
  than closing the connection.
  #10645

• Cranelift's single-pass allocator has been disabled due to being unable to
  support internal refactorings in preparation for the WebAssembly exceptions
  proposal. Re-enabling this allocator is tracked at
  regalloc2#217 for
  those interested.
  #10554

• Wasmtime's {Array,Extern,Struct}Ref functions will now automatically trigger
  a GC.
  #10560

• Wasmtime's GC heaps now use the same translation techniques as linear memories
  meaning they have far fewer bounds-checks than before.
  #10503

• Wasmtime's implementation of WASIp2 has moved to wasmtime_wasi::p2 from the
  root of the crate.
  #10073

• Wasmtime will no longer emit calls to Cranelift-defined "libcalls" and instead
  everything goes through Wasmtime's libcall mechanism instead, paving the way
  for a future change for more efficient stack limit checking in wasm. This can
  also improve deserialize-from-disk times and improve page cache usage for
  modules that use libcalls as relocations are no longer necessary.
  #10657

• Configuration of caching can now be done through an API instead of exclusively
  through a configuration file. Additionally cache-related APIs in Config have
  changed.
  #10665

• Resources in the Component Model are now stored in a single table per-instance
  instead of per-type tables. Guests will see a different pattern of index
  allocation but this is not expected to cause any issues at runtime.
  #10701

Fixed

• Some math intrinsics have been fixed when compiled by Rust 1.87+.
  #10534

• Component model libcalls correctly handle platform-specific argument extension
  in ABIs.
  #10540

• An off-by-one issue with DWARF debuginfo has been fixed.
  #10570

• The Config::target method is no longer gated by a #[cfg] for an enabled
  compiler, it can be used when only the runtime feature is available.
  #10618

• An issue with "simulated" DWARF has been fixed.
  #10681

• C/C++ headers are now tested that they can be included in isolation, and a
  number of issues have been fixed.
  #10694

v32.0.0: Release Wasmtime 32.0.0 (#10617)

32.0.0

Released 2025-04-21.

Added

• {Module,Component}::deserialize_raw can now be used to deserialize an
  in-memory module while relying on external management of the memory.
  #10321

• An initial implementation of wasi-tls has been added.
  #10249

• The wasmtime CLI now supports hexadecimal integer CLI arguments.
  #10360

• Cranelift now supports a log2_min_function_alignment flag.
  #10391

• A new wasmtime objdump subcommand has been added to help explore and debug
  *.cwasm files.
  #10405

• Support for the pooling allocator has been added to the C API.
  #10484

• Support for the guest profiler with the component model has been added.
  #10507

Changed

• Cranelift MemFlags now has a can_move flag which restricts whether a load
  or store can be moved.
  #10340

• The .text size of Pulley *.cwasm files should be smaller with less
  padding.
  #10285

• The wasmtime serve subcommand now implements a graceful shutdown on ctrl-c.
  #10394

• Stack maps used for GC are now stored in a serialized binary format that is
  faster to deserialize.
  #10404

• The aegraph implementation in Cranelift has been simplified to remove the
  union-find and canonical eclass IDs.
  #10471

• The store_list and load_list helpers have been specialized in components
  for f32 and f64.
  #9892

• Cranelift now removes block params on critical-edge blocks.
  #10485

• The Linker::define_unknown_imports_as_default_values API now supports
  defining defaults for more kinds of items.
  #10500

• Wasmtime now requires Rust 1.84.0 to compile.
  #10520

Fixed

• Winch compilation of extadd instructions has been fixed.
  #10337

• Fix an issue with DRC collector's barriers.
  #10371

• Loads on (ref null none) that can trap are now performed.
  #10372

• Fix reference count management in AnyRef::from_raw.
  #10374

• An issue with multi-value returns in Winch has been fixed.
  #10370

• A panic at compile-time from an overflowing shift has been fixed when
  targeting aarch64.
  #10382

• The wasmtime serve command no longer panics when handle returns before
  calling set.
  #10387

• Winch compilation of replace_lane instructions with floats has been fixed.
  #10393

• An invalid integer-shift optimization on vector types has been removed.
  #10413

• The DWARF loclist to exprloc optimization has been fixed.
  #10400

• Objects in the DRC collector are now transitively dec-ref's when collected.
  #10401

• A bug with GC rec gropus and registration in an Engine has been fixed.
  #10435

• A bug related to GC arrays of GC refs misreported their count of GC edges has
  been fixed.
  #10453

• A bug related to appropriately adding stack maps for all GC variables has been
  fixed.
  #10456
  #10468

• A bug with array.fill has been fixed.
  #10470

• GC structs are no longer reordered to optimize their size to fix subtyping.
  #10463

• Panics related to exceptions and components being mixed has been fixed.
  #10473

• Winch stack parameter alignment has been fixed.
  #10513

• Rendering inline function frames in a trap backtrace has been fixed.
  #10523

v31.0.0: Release Wasmtime 31.0.0 (#10428)

31.0.0

Released 2025-03-20.

Added

• Winch's implementation of the SIMD proposal for WebAssembly is now
  feature-complete (but still being fuzzed).
  #10180
  #10170
  #10203
  #10202
  #10210
  #10213
  #10224
  #10205
  #10226
  #10228
  #10236
  #10241
  #10243
  #10247
  #10271
  #10284
  #10288
  #10296

• The pytorch implementation in wasmtime-wasi-nn now has GPU support.
  #10204

• Cranelift now supports emitting the AArch64 extr instruction.
  #10229

• Cranelift now supports emitting the x64 shld instruction.
  #10233

• Initial support for the stack-switching proposal has started to land, but it
  is not complete just yet.
  #10251
  #10265
  #10255

Changed

• Pulley's implementation of loads/stores to linear memory has changed to
  better support optimizations and reduction of interpreter opcodes in the
  final binary.
  #10154

• Cranelift's verifier now ensures that integers used as address types have the
  correct width.
  #10209

• Wasmtime and Cranelift's minimum supported version of Rust is now 1.83.0.
  #10264

• Wasmtime now mentions the filename when the input cannot be opened on the CLI.
  #10292

• All types are now generated in component::bindgen!, even if they're not
  reachable.
  #10311

• Tables allocated with the system allocator now use alloc_zeroed (aka
  calloc) for allocation.
  #10313

Fixed

• GC: the is-null-or-i31ref checks have been fixed.
  #10221

• GC: an incorrect assertion and canonicalized types for runtime usage has been
  fixed.
  #10223

• GC: subtype checks for imported globals during instantiation have been fixed.
  #10304

• GC: exposing references to wasm in the gc_alloc_raw libcall has been fixed.
  #10322

• Winch's fuel checks correctly sync fuel before the check now.
  #10231

• Winch's treatment of stores and other trapping ops has been fixed on AArch64.
  #10201

• Winch's handling of the shadow stack pointer has been fixed on AArch64.
  #10263

• Winch's handling of address calculations has been fixed on AArch64.
  #10297

• Winch's handling of multivalue return of constants has ben fixed.
  #10315

v30.0.2: Release Wasmtime 30.0.2 (#10294)

30.0.2

Released 2025-02-25.

Fixed

• MinGW C API builds are now built with a newer version of GCC which seems to
  fix an issue caused by #9929.
  #10290

Changed

• The cranelift-codegen crate now no longer depends on arbitrary, a
  now-unnecessary dependency.
  #10217

v30.0.1: Release Wasmtime 30.0.1 (#10272)

30.0.1

Released 2025-02-21.

Fixed

• Fixes an issue building the cranelift-assembler-x64 crate on Windows
  when the Rust toolchain is on a different drive than the project using
  wasmtime. For more details, see the Zulip discussion. #10270

v30.0.0: Release Wasmtime 30.0.0 (#10250)

30.0.0

Released 2025-02-20.

Added

• New wasmtime-wasi-io crate provides a #![no_std] wasi:io implementation,
  factored out of wasmtime-wasi. Users of wasmtime-wasi don't have to
  depend on this new crate.
  #10036

• Wasmtime's interpreter, Pulley, is now complete and has been listed as
  tier 2.
  #9897
  #9884
  #9943
  #9944
  #9983
  #9966
  #9935
  #10034
  #10057
  #10095

• Wasmtime's CI now checks that the repository builds for aarch64-apple-ios.
  Note that no tests are run for this target, so it's still tier 3.
  #9888

• Winch's support for AArch64 and simd on x64 have continued to progress
  well. Winch additionally now fully supports the threads WebAssembly
  proposal.
  #9889
  #9970
  #9950
  #9987
  #9990
  #9959
  #10008
  #10028
  #10029
  #10023
  #10042
  #10050
  #10039
  #10082
  #10092
  #10109
  #10148
  #10147

• The memory64 WebAssembly feature is now enabled by default. This WebAssembly
  proposal is now considered a tier 1 feature.
  #9937
  #10159

• Wasmtime's full test suite and CI now includes 32-bit platforms such as x86
  and armv7 Linux. These platforms have been added to tier 3 status and use
  Pulley as their execution backend.
  #10025

• Initial experimental support for WASIp3 and async features of the Component
  Model have started to land. These features are not yet ready for
  general-purpose use.
  #10044
  #10047
  #10083
  #10103

• The wasmtime CLI now supports using a TOML configuration file via --config
  in addition to CLI options.
  #9811
  #10132

• Initial support for a new assembler on x64 has been added.
  #10110
  #10178

Changed

• wasmtime-wasi split the WasiView trait into IoView and WasiView, and
  wasmtime-wasi-http re-uses IoView in WasiHttpView. Details on porting
  for embedders in PR.
  #10016

• wasmtime-wasi renamed some exported types and traits. Embedders which use
  Pollable, InputStream, OutputStream, Subscribe, HostInputStream,
  HostOutputStream, PollableFuture, or ClosureFuture from that crate
  will need to rename those imports to their new names, describe in PR.
  #10036

• Components using a 64-bit linear memory should never have worked before, but
  they're now rejected earlier in the validation process.
  #9952

• Module validation is now deterministic in the face of multiple errors.
  #9947

• Wasmtime's minimum supported version of Rust is now 1.82.0.
  #9956

• Cranelift will now deduplicate trap[n]z instructions.
  #10004

• The --emit-clif option to wasmtime compile now emits post-optimization
  CLIF.
  #10011

• The signals-based-traps Cargo feature has been removed in favor of
  auto-detection of available features based on the #[cfg] directives
  available for the target platform.
  #9941

• The async_stack_zeroing configuration knob now covers all stack allocations,
  not just those from the pooling allocator.
  #10027

• Wasmtime should work-by-default on more platforms, even those where Cranelift
  has no support for the architecture. This is done by ensuring some
  architecture and platform-specific bits are removed on unknown platforms (and
  Pulley is used instead).
  #10107

• Wasmtime now compiles on platforms missing 64-bit atomics.
  #10134

Fixed

• Fixed a missing case for Ref::matches_ty should return true.
  #9985

• A bug with using the single_pass register allocation algorithm on x64/s390x
  has been fixed by refactoring how branches are represented.
  #10086
  #10087

• A bug with argument extensions on riscv64 has been fixed.
  #10069

• The PartialEq implementation for RegisteredType has been fixed.
  #10091

• The output of component::bindgen! now works with #![no_std] crates.
  #10105

• Fix wasmtime wast when combined with --fuel.
  #10121

• The wat feature of the C API is now plumbed correctly in a few more
  locations.
  #10124

• Spurious wake-ups in blocking_* methods of InputStream and OutputStream
  have been fixed.
  #10113