Stream: git-wasmtime

Topic: wasmtime / issue #13327 Winch x64: panic compiling`i32.at...

Wasmtime GitHub notifications bot (May 08 2026 at 17:41):

alexcrichton opened issue #13327:

This input:

(module
  (memory 2 )
  (func (export "f") (param i32) (result i32)
    local.get 0
    i32.atomic.load16_u offset=65536
  )
)

currently fails with:

$ cargo run compile -C compiler=winch foo.wat
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.17s
     Running `target/debug/wasmtime compile -C compiler=winch foo.wat`

thread '<unnamed>' (1303362) panicked at winch/codegen/src/isa/x64/asm.rs:1196:81:
called `Result::unwrap()` on an `Err` value: TryFromIntError(())
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

cc @saulecabrera

Wasmtime GitHub notifications bot (May 08 2026 at 17:41):

alexcrichton added the winch label to Issue #13327.

Wasmtime GitHub notifications bot (May 08 2026 at 18:30):

alexcrichton commented on issue #13327:

A slight variant of this:

(module
  (memory 2)
  (func (export "f") (param i32) (result i32)
    local.get 0
    i32.atomic.load16_u offset=0x80000000
  )
)

panics with:

$ cargo run compile -C compiler=winch foo.wat
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.12s
     Running `/home/alex/code/wasmtime2/target/debug/wasmtime compile -C compiler=winch foo.wat`

thread '<unnamed>' (1320511) panicked at cranelift/codegen/src/isa/x64/inst/mod.rs:164:9:
assertion failed: dst_size.is_one_of(&[OperandSize::Size32, OperandSize::Size64])
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

Wasmtime GitHub notifications bot (May 11 2026 at 11:31):

saulecabrera commented on issue #13327:

Taking a look at this one this week.

Wasmtime GitHub notifications bot (May 11 2026 at 18:18):

saulecabrera commented on issue #13327:

Opened https://github.com/bytecodealliance/wasmtime/pull/13337

Wasmtime GitHub notifications bot (May 11 2026 at 20:24):

saulecabrera closed issue #13327:

This input:

(module
  (memory 2 )
  (func (export "f") (param i32) (result i32)
    local.get 0
    i32.atomic.load16_u offset=65536
  )
)

currently fails with:

$ cargo run compile -C compiler=winch foo.wat
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.17s
     Running `target/debug/wasmtime compile -C compiler=winch foo.wat`

thread '<unnamed>' (1303362) panicked at winch/codegen/src/isa/x64/asm.rs:1196:81:
called `Result::unwrap()` on an `Err` value: TryFromIntError(())
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

cc @saulecabrera

Wasmtime GitHub notifications bot (May 11 2026 at 20:24):

saulecabrera commented on issue #13327:

Fixed in https://github.com/bytecodealliance/wasmtime/pull/13337

Last updated: Jun 01 2026 at 09:49 UTC