Released 2022-01-05.
-
Compiled wasm modules may now optionally omit debugging information about mapping addresses to source locations, resulting in smaller binaries. #3598
-
The WebAssembly SIMD proposal is now enabled by default. #3601
Released 2022-01-04.
-
Cranelift: remove recently-added build dependency on
sha2
to allow usage in some dependency-sensitive environments, by computing ISLE manifest hashes with a different hash function. #3619 -
Cranelift: fixed 8- and 16-bit behavior of popcount (bit population count) instruction. Does not affect Wasm frontend. #3617
-
Cranelift: fixed miscompilation of 8- and 16-bit bit-rotate instructions. Does not affect Wasm frontend. #3610
Released 2021-12-13.
-
A new configuration option has been added to force using a "static" memory style to automatically limit growth of memories in some configurations. #3503
-
The
InstancePre<T>
type now implementsClone
. #3510 -
Cranelift's instruction selection process has begun to be migrated towards the ISLE compiler and definition language. #3506
-
A
pooling-allocator
feature has been added, which is on-by-default, to disable the pooling allocator at compile time. #3514
-
A possible panic when parsing a WebAssembly
name
section has been fixed. #3509 -
Generating native DWARF information for some C-produced modules has been fixed, notably those where there may be DWARF about dead code. #3498
-
A number of SIMD code generation bugs have been fixed in the x64 backend by migrating their lowerings to ISLE.
Released 2021-10-29.
-
New
Func::new_unchecked
andFunc::call_unchecked
APIs have been added with accompanying functions in the C API to improve the performance of calls into wasm and the host in the C API. #3350 -
Release binaries are now available for the s390x-unknown-linux-gnu architecture. #3372
-
A new
ResourceLimiterAsync
trait is added which allows asynchronous blocking of WebAssembly on instructions such asmemory.grow
. #3393
-
The
Func::call
method now takes a slice to write the results into rather than returning a boxed slice. #3319 -
Trampolines are now covered when jitdump profiling is enabled. #3344
-
Debugging with GDB has been fixed on Windows. #3373
-
Some quadradic behavior in Wasmtime's compilation of modules has been fixed. #3469 #3466
-
Bounds-checks for wasm memory accesses in certain non-default configurations have been fixed to correctly allow loads at the end of the address space. #3462
-
When type-checking memories and tables for satisfying instance imports the runtime size of the table/memory is now consulted instead of the object's original type. #3450
Released 2021-09-17.
-
CVE-2021-39216: Fixed a use after free passing
externref
s to Wasm in Wasmtime. -
CVE-2021-39218: Fixed an out-of-bounds read/write and invalid free with
externref
s and GC safepoints in Wasmtime. -
CVE-2021-39219: Fixed a bug where using two different
Engine
s with the sameLinker
-define functions caused unsafety withoutunsafe
blocks.
-
Added experimental support for the in-progress 64-bit memories Wasm proposal.
-
Added support to build Wasmtime without the compiler. This lets you run pre-compiled Wasm modules, without the ability (or potential attack surface) of compiling new Wasm modules. The compilation functionality is gated by the on-by-default
cranelift
cargo feature. -
Added support for NaN canonicalization with SIMD vectors.
-
Added support for differential fuzzing against V8's Wasm engine.
-
Added support for fuzzing against the Wasm spec interpreter.
-
Enabled SIMD fuzzing on oss-fuzz.
-
A variety of performance improvements to loading pre-compiled modules.
-
A variety of performance improvements to function calls, both through Rust and the C API.
-
Leaf functions that do not use the stack no longer bump the frame pointer on aarch64 and s390x.
-
Many updates and expanded instruction support to the in-progress CLIF interpreter.
-
Expanded fuzzing of reference types and GC.
-
A number of fixes to both aarch64 and x86_64 support for the Wasm SIMD proposal and the underlying CLIF vector instructions.
-
Fixed a potential infinite loop in the SSA computation for
cranelift-frontend
. This was not reachable fromcranelift-wasm
or Wasmtime, but might have affected general Cranelift users.
- The
wasmtime wasm2obj
subcommand has been removed. Generating raw object files for linking natively is no longer supported. Use thewasmtime compile
subcommand to pre-compile a Wasm module andwasmtime run
to run pre-compiled Wasm modules.
Released 2021-08-02.
-
Instance exports are now loaded lazily from instances instead of eagerly as they were before. This is an internal-only change and is not a breaking change. #2984
-
All linear memories created by Wasmtime will now, by default, have guard pages in front of them in addition to after them. This is intended to help mitigate future bugs in Cranelift, should they arise. #2977
-
Linear memories now correctly support a maximum size of 4GB. Previously, the limit field was 32 bits, which did not properly support a full 4GB memory. This update is also a necessary change in preparation for future memory64 support. #3013 #3134
-
Injection counts of fuel into a
wasmtime::Store
now uses a u64 instead of a u32. #3048
-
Support for
i128
has improved in the AArch64 backend. #2959 #2975 #2985 #2990 #3002 #3004 #3005 #3008 #3027 -
The
wasmtime::Linker
type now implementsClone
. #2993 -
Support for the SIMD proposal on both x86_64 and AArch64 has improved. On x86_64, all SIMD opcodes are now supported. #2997 #3035 #2982 #3084 #3082 #3107 #3105 #3114 #3070 #3126
-
A
Trap
can now display its reason without also displaying the backtrace. #3033 -
An initiall fuzzer for CLIF has been added. #3038
-
High-level architecture documentation has been added for Wasmtime. #3019
-
Support for multi-memory can now be configured in Wasmtime's C API. #3071
-
The
wasmtime
crate now supports aposix-signals-on-macos
feature to force the usage of signals instead of mach ports to handle traps on macOS. #3063 -
Wasmtime's C API now has a
wasmtime_trap_code
function to get the raw trap code, if present, for a trap. #3086 -
Wasmtime's C API now has a
wasmtime_linker_define_func
function to define a store-independent function within a linker. #3122 -
A
wasmtime::Linker::module_async
function was added as the asynchronous counterpart towasmtime::Linker::module
. #3121
-
Compiling the
wasmtime
crate into adylib
crate type has been fixed. #3010 -
The enter/exit hooks for WebAssembly are now executed for an instance's
start
function, if present. #3001 -
Some WASI functions in
wasi-common
have been fixed for big-endian platforms. #3016 -
Wasmtime no longer erroneously assumes that all custom sections may contain DWARF information, reducing instances of
Trap
'sDisplay
implementation providing misleading information to set an env var to get more information. #3083 -
Some issues with parsing DWARF debug information have been fixed. #3116
Released 2021-06-09.
- Breaking: Wasmtime's embedding API has been redesigned, as specified in RFC
11. Rust users can now enjoy easier times with
Send
andSync
, and all users can now more clearly manage memory, especially in the C API. Language embeddings have been updated to the new API as well. #2897
-
A new
InstancePre
type, created withLinker::instantiate_pre
, has been added to perform type-checking of an instance once and reduce the work done for each instantiation of a module: #2962 -
Deserialization of a module can now optionally skip checking the wasmtime version string: #2945
-
A method has been exposed to frontload per-thread initialization costs if the latency of every last wasm call is important: #2946
-
Hooks have been added for entry/exit into wasm code to allow embeddings to track time and other properties about execution in a wasm environment: #2952
- Multiple returns on macOS AArch64 have been fixed: #2956
Released 2021-05-21.
- Fixed a security issue in Cranelift's x64 backend that could result in a heap sandbox escape due to an incorrect sign-extension: #2913.
-
Support for IBM z/Archiecture (
s390x
) machines in Cranelift and Wasmtime: #2836, #2837, #2838, #2843, #2854, #2870, #2871, #2872, #2874. -
Improved async support in wasi-common runtime: #2832.
-
Added
Store::with_limits
,StoreLimits
, andResourceLimiter
to the Wasmtime API to help with enforcing resource limits at runtime. TheResourceLimiter
trait can be implemented by custom resource limiters to decide if linear memories or tables can be grown. -
Added
allow-unknown-exports
option for the run command: #2879. -
Added API to notify that a
Store
has moved to a new thread: #2822. -
Documented guidance around using Wasmtime in multithreaded contexts: #2812. In the future, the Wasmtime API will change to allow some of its core types to be Send/Sync; see the in-progress #2897 for details.
-
Support calls from native code to multiple-return-value functions: #2806.
- Breaking:
Memory::new
has been changed to returnResult
as creating a host memory object is now a fallible operation when the initial size of the memory exceeds the store limits.
-
Many instruction selection improvements on x64 and aarch64: #2819, #2828, #2823, #2862, #2886, #2889, #2905.
-
Improved performance of Wasmtime runtime substantially: #2811, #2818, #2821, #2847, #2900.
-
Fixed WASI issue with file metadata on Windows: #2884.
-
Fixed an issue with debug info and an underflowing (trapping) offset: #2866.
-
Fixed an issue with unwind information in the old x86 backend: #2845.
-
Fixed i32 spilling in x64 backend: #2840.
Released 2021-04-05.
-
Added the
wasmtime compile
command to support AOT compilation of Wasm modules. This adds theEngine::precompile_module
method. Also added theConfig::target
method to change the compilation target of the configuration. This can be used in conjunction withEngine::precompile_module
to target a different host triple than the current one. #2791 -
Support for macOS on aarch64 (Apple M1 Silicon), including Apple-specific calling convention details and unwinding/exception handling using Mach ports. #2742, #2723
-
A number of SIMD instruction implementations in the new x86-64 backend. #2771
-
Added the
Config::cranelift_flag_enable
method to enable setting Cranelift boolean flags or presets in a config. -
Added CLI option
--cranelift-enable
to enable boolean settings and ISA presets. -
Deduplicate function signatures in Wasm modules. #2772
-
Optimize overheads of calling into Wasm functions. #2757, #2759
-
Improvements related to Module Linking: compile fewer trampolines;
-
Re-export sibling crates from
wasmtime-wasi
to make embedding easier without needing to match crate versions. #2776
-
Switched the default compiler backend on x86-64 to Cranelift's new backend. This should not have any user-visible effects other than possibly runtime performance improvements. The old backend is still available with the
old-x86-backend
feature flag to thecranelift-codegen
orwasmtime
crates, or programmatically withBackendVariant::Legacy
. We plan to maintain the old backend for at least one more release and ensure it works on CI. #2718 -
Breaking:
Module::deserialize
has been removed in favor ofModule::new
. -
Breaking:
Config::cranelift_clear_cpu_flags
was removed. UseConfig::target
to clear the CPU flags for the host's target. -
Breaking:
Config::cranelift_other_flag
was renamed toConfig::cranelift_flag_set
. -
CLI changes:
- Wasmtime CLI options to enable WebAssembly features have been replaced with
a singular
--wasm-features
option. The previous options are still supported, but are not displayed in help text. - Breaking: the CLI option
--cranelift-flags
was changed to--cranelift-set
. - Breaking: the CLI option
--enable-reference-types=false
has been changed to--wasm-features=-reference-types
. - Breaking: the CLI option
--enable-multi-value=false
has been changed to--wasm-features=-multi-value
. - Breaking: the CLI option
--enable-bulk-memory=false
has been changed to--wasm-features=-bulk-memory
.
- Wasmtime CLI options to enable WebAssembly features have been replaced with
a singular
-
Improved error-reporting in wiggle. #2760
-
Make WASI sleeping fallible (some systems do not support sleep). #2756
-
WASI: Support
poll_oneoff
with a sleep. #2753 -
Allow a
StackMapSink
to be passed when defining functions withcranelift-module
. #2739 -
Some refactoring in new x86-64 backend to prepare for VEX/EVEX (e.g., AVX-512) instruction encodings to be supported. #2799
-
Fixed a corner case in
srem
(signed remainder) in the new x86-64 backend:INT_MIN % -1
should return0
, rather than trapping. This only occurred whenavoid_div_traps == false
was set by the embedding. #2763 -
Fixed a memory leak of the
Store
when an instance traps. #2803 -
Fixed memory-initialization bug in uffd allocator that could copy into the wrong destination under certain conditions. Does not affect the default wasmtime instance allocator. #2801
-
Fix printing of float values from the Wasmtime CLI. #2797
-
Remove the ability for the
Linker
to instantiate modules with duplicate import strings of different types. #2789
Released 2021-03-16.
-
An implementation of a pooling instance allocator, optionally backed by
userfaultfd
on Linux, was added to improve the performance of embeddings that instantiate a large number of instances continuously. #2518 -
Host functions can now be defined on
Config
to share the function across allStore
objects connected to anEngine
. This can improve the time it takes to instantiate instances in a short-livedStore
. #2625 -
The
Store
object now supports having typed values attached to it which can be retrieved from host functions. #2625 -
The
wiggle
code generator now supportsasync
host functions. #2701
-
The
Func::getN{,_async}
APIs have all been removed in favor of a newFunc::typed
API which should be more compact in terms of API surface area as well as more flexible in how it can be used. #2719 -
Engine::new
has been changed from returningEngine
to returninganyhow::Result<Engine>
. Callers ofEngine::new
will need to be updated to use the?
operator on the return value or otherwise unwrap the result to get theEngine
.
- Interpretation of timestamps in
poll_oneoff
for WASI have been fixed to correctly use nanoseconds instead of microseconds. #2717
Released 2021-03-04.
- Implement support for
async
functions in Wasmtime #2434
- Fix preservation of the sigaltstack on macOS #2676
- Fix incorrect semver dependencies involving fs-set-times. #2705
- Fix some
i128
shift-related bugs in x64 backend. #2682 - Fix incomplete trap metadata due to multiple traps at one address #2685
Released 2021-02-16.
- Support for limiting WebAssembly execution with fuel was added, including support in the C API. #2611 #2643
- Wasmtime now has more knobs for limiting memory and table allocations #2617
- Added a method to share
Config
across machines #2608 - Added a safe memory read/write API #2528
- Added support for the experimental wasi-crypto APIs #2597
- Added an instance limit to
Config
#2593 - Implemented module-linking's outer module aliases #2590
- Cranelift now supports 128-bit operations for the new x64 backend. #2539
- Cranelift now has detailed debug-info (DWARF) support in new backends (initially x64). #2565
- Cranelift now uses the
POPCNT
,TZCNT
, andLZCNT
, as well as SSE 4.1 rounding instructions on x64 when available. - Cranelift now uses the
CNT
, instruction on aarch64 when available.
-
A new WASI implementation built on the new
cap-std
crate was added, replacing the previous implementation. This brings improved robustness, portability, and performance. -
wasmtime_wasi::WasiCtxBuilder
moved towasi_cap_std_sync::WasiCtxBuilder
. -
The WebAssembly C API is updated, with a few minor API changes #2579
- Fixed a panic in WASI
fd_readdir
on large directories #2620 - Fixed a memory leak with command modules #2017
Released 2021-01-07.
-
Experimental support for the module-linking proposal was added. #2094
-
Added support for the reference types proposal on the aarch64 architecture. #2410
-
Fixed an issue where the
select
instruction didn't acceptv128
SIMD operands. #2391 -
Fixed an issue where Wasmtime could potentially use the wrong stack map during GCs, leading to a panic. #2396
-
Fixed an issue where if a host-defined function erroneously returned a value from a different store, that value would be leaked. #2424
-
Fixed a bug where in certain cases if a module's instantiation failed, it could leave trampolines in the store that referenced the no-longer-valid instance. These trampolines could be reused in future instantiations, leading to use after free bugs. #2408
-
Fixed a miscompilation on aarch64 where certain instructions would read
SP
instead of the zero register. This could only affect you if you explicitly enabled the Wasm SIMD proposal. #2548
Released 2020-11-05.
-
Experimental support for the multi-memory proposal was added. #2263
-
The
Trap::trap_code
API enables learning what kind of trap was raised. #2309
-
WebAssembly module validation is now parallelized. #2059
-
Documentation is now available at docs.wasmtime.dev. #2317
-
Windows now compiles like other platforms with a huge guard page instead of having its own custom limit which made modules compile and run more slowly. #2326
-
The size of the cache entry for serialized modules has been greatly reduced. #2321 #2322 #2324 #2325
-
The
FuncType
API constructor and accessors are now iterator-based. #2365
- A panic in compiling reference-types-using modules has been fixed. #2350
Released 2020-09-23.
-
Support for explicitly serializing and deserializing compiled wasm modules has been added. #2020
-
A
wasmtime_store_gc
C API was added to run GC forexternref
. #2052 -
Support for atomics in Cranelift has been added. Support is not fully implemented in Wasmtime at this time, however. #2077
-
The
Caller::get_export
function is now implemented forFunc
references as well. #2108
-
Leaks in the C API have been fixed. #2040
-
The
wasm_val_copy
C API has been fixed for reference types. #2041 -
Fix a panic with
Func::new
and reference types when the store doesn't have reference types enabled. #2039
Released 2020-07-14.
-
The WebAssembly reference-types proposal is now supported in Wasmtime and the C API. #1832, #1882, #1894, #1901, #1923, #1969, #1973, #1982, #1984, #1991, #1996
-
The [WebAssembly simd proposal's][simd] spec tests now pass in Wasmtime. #1765, #1876, #1941, #1957, #1990, #1994
-
Wasmtime can now be compiled without the usage of threads for parallel compilation, although this is still enabled by default. #1903
-
The C API is now documented. #1928, #1959, #1968
-
A
wasmtime_linker_get_one_by_name
function was added to the C API. #1897 -
A
wasmtime_trap_exit_status
function was added to the C API. #1912 -
Compilation for the
aarch64-linux-android
target should now work, although keep in mind this platform is not fully tested still. #2002
-
Runtime warnings when using Wasmtime on musl have been fixed. #1914
-
A bug affecting Windows unwind information with functions that have spilled floating point registers has been fixed. #1983
- Wasmtime's default branch and development now happens on the
main
branch instead ofmaster
. #1924
-
The "host info" support in the C API has been removed since it was never fully or correctly implemented. #1922
-
Support for the
*_same
functions in the C API has been removed in the same vein as the host info APIs. #1926
Release 2020-06-09.
The WasmTy
trait is now implemented for u32
and u64
.
Released 2020-06-01.
-
The Commands and Reactors ABI is now supported in the Rust API.
Linker::module
loads a module and automatically handles Commands and Reactors semantics.
The Table::grow
function now returns the previous table size, making it consistent
with the table.grow
instruction.
New Wasmtime-specific C APIs for working with tables were added which provide more
detailed error information and which make growing a table more consistent with the
table.grow
instruction as well.
The C API now includes support for enabling logging in Wasmtime.
The WASI proc_exit
function no longer exits the host process. It now unwinds the
callstack back to the wasm entrypoint, and the exit value is available from the
Trap::i32_exit_status
method.
The WebAssembly multi-value proposal is now enabled by default.
The Rust API does not require a store provided during Module::new
operation. The Module
can be send accross threads and instantiate for a specific store. The Instance::new
now requires the store.
Released 2020-04-29.
-
The
Instance
struct has new accessors,get_func
,get_table
,get_memory
, andget_global
for quickly looking up exported functions, tables, memories, and globals by name. #1524 -
The C API has a number of new
wasmtime_*
functions which return error objects to get detailed error information when an API fails. #1467 -
Users now have fine-grained control over creation of instances of
Memory
with a newMemoryCreator
trait. #1400 -
Go bindings for Wasmtime are now available. #1481
-
APIs for looking up values in a
Linker
have been added. #1480 -
Preliminary support for AArch64, also known as ARM64. #1581
-
Instance::exports
now returnsExport
objects which contain thename
s of the exports in addition to theirExtern
definitions, so it's no longer necessary to useModule::exports
to obtain the export names. #1524 -
The
Func::call
API has changed its error type fromTrap
toanyhow::Error
to distinguish between wasm traps and runtime violations (like the wrong number of parameters). #1467 -
A number of
wasmtime_linker_*
andwasmtime_config_*
C APIs have new type signatures which reflect returning errors. #1467 -
Bindings for .NET have moved to https://github.com/bytecodealliance/wasmtime-dotnet. #1477
-
Passing too many imports to
Instance::new
is now considered an error. #1478
- Spurious segfaults due to out-of-stack conditions when handling signals have been fixed. #1315
Released 2020-03-31.
Full release produced for all artifacts to account for hiccups in 0.13.0 and 0.14.0.
This version ended up not getting a full release
Fix build errors in wasi-common on Windows.
Released 2020-03-24.
-
Lots of documentation of
wasmtime
has been updated. Be sure to check out the book and API documentation! -
All wasmtime example programs are now in a top-level
examples
directory and are available in both C and Rust. #1286 -
A
wasmtime::Linker
type was added to conveniently link link wasm modules together and create instances that reference one another. #1384 -
Wasmtime now has "jitdump" support enabled by default which allows profiling wasm code on linux. #1310
-
The
wasmtime::Caller
type now exists as a first-class way to access the caller's exports, namely memory, when implementing host APIs. This can be the first argument of functions defined withFunc::new
orFunc::wrap
which allows easily implementing methods which take a pointer into wasm memory. Note that this only works for accessing the caller'sMemory
for now and it must be exported. This will eventually be replaced with a more general-purpose mechanism like interface types. #1290 -
The bulk memory proposal has been fully implemented. #1264 #976
-
Virtual file support has been added to
wasi-common
. #701 -
The C API has been enhanced with a Wasmtime-specific
wasmtime_wat2wasm
to parse*.wat
files via the C API. #1206
-
The
wast
andwasm2obj
standalone binaries have been removed. They're available via thewasmtime wast
andwasmtime wasm2obj
subcommands. #1372 -
The
wasi-common
crate now uses the newwiggle
crate to auto-generate a trait which is implemented for the current wasi snapshot. #1202 -
Wasmtime no longer has a dependency on a C++ compiler. #1365
-
The
Func::wrapN
APIs have been consolidated into oneFunc::wrap
API. #1363 -
The
Callable
trait has been removed and nowFunc::new
takes a closure directly. #1363 -
The Cranelift repository has been merged into the Wasmtime repository.
-
Support for interface types has been temporarily removed. #1292
-
The exit code of the
wasmtime
CLI has changed if the program traps. #1274 -
The
wasmtime
CLI now logs to stderr by default and the-d
flag has been renamed to--log-to-file
. #1266 -
Values cannot cross
Store
objects, meaning you can't instantiate a module with values from different stores nor pass values from different stores into methods. #1016
Released 2020-02-26.
-
Support for the WebAssembly text annotations proposal has been added. #998
-
An initial C API for instantiating WASI modules has been added. #977
-
A new suite of
Func::getN
functions have been added to thewasmtime
API to call statically-known function signatures in a highly optimized fashion. #955 -
Initial support for profiling JIT code through perf jitdump has been added. #360
-
More CLI flags corresponding to proposed WebAssembly features have been added. #917
-
The
wasmtime
CLI as well as embedding API will optimize WebAssembly code by default now. #973 #988 -
The
verifier
pass in Cranelift is now no longer run by default when using the embedding API. #882
-
Code caching now accurately accounts for optimization levels, ensuring that if you ask for optimized code you're not accidentally handed unoptimized code from the cache. #974
-
Automated releases for tags should be up and running again, along with automatic publication of the
wasmtime
Python package. #971