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

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Release notes for previous releases of Wasmtime can be found on the respective release branches of the Wasmtime repository.

• 30.0.x
• 29.0.x
• 28.0.x
• 27.0.x
• 26.0.x
• 25.0.x
• 24.0.x
• 23.0.x
• 22.0.x
• 21.0.x
• 20.0.x
• 19.0.x
• 18.0.x
• 17.0.x
• 16.0.x
• 15.0.x
• 14.0.x
• 13.0.x
• 12.0.x
• 11.0.x
• 10.0.x
• 9.0.x
• 8.0.x
• 7.0.x
• 6.0.x
• 5.0.x
• 4.0.x
• 3.0.x
• 2.0.x
• 1.0.x
• 0.40.x
• 0.39.x
• 0.38.x
• 0.37.x
• 0.36.x
• 0.35.x
• 0.34.x
• 0.33.x
• 0.32.x (and prior)