Stream: git-wasmtime

Topic: wasmtime / issue #12808 An assertion failed with config.g...

view this post on Zulip Wasmtime GitHub notifications bot (Mar 20 2026 at 06:06):

Destructor17 opened issue #12808:

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Test Case

main.wasm.gz

Steps to Reproduce

let engine = wasmtime::Engine::new(wasmtime::Config::new().guest_debug(true)).unwrap();
wasmtime::Module::from_file(&engine, "path/to/main.wasm").unwrap();

Expected Results

Module compiles successfully

Actual Results

An assertion failed

thread '<unnamed>' (62495) panicked at external/wasmtime/crates/cranelift/src/translate/stack.rs:548:9:
assertion failed: self.stack_shape.is_empty() || self.stack_shape.len() == self.stack.len()

Versions and Environment

Wasmtime version or commit: 4834727

Operating system: Ubuntu 25.10

Architecture: x86_64

Extra Info

Backtrace (not attached, sorry) mentions debug_tags from commit above

view this post on Zulip Wasmtime GitHub notifications bot (Mar 20 2026 at 06:06):

Destructor17 added the bug label to Issue #12808.

view this post on Zulip Wasmtime GitHub notifications bot (Mar 20 2026 at 06:07):

Destructor17 edited issue #12808:

Test Case

main.wasm.gz

Steps to Reproduce

let engine = wasmtime::Engine::new(wasmtime::Config::new().guest_debug(true)).unwrap();
wasmtime::Module::from_file(&engine, "path/to/main.wasm").unwrap();

Expected Results

Module compiles successfully

Actual Results

An assertion failed

thread '<unnamed>' (62495) panicked at external/wasmtime/crates/cranelift/src/translate/stack.rs:548:9:
assertion failed: self.stack_shape.is_empty() || self.stack_shape.len() == self.stack.len()

Versions and Environment

Wasmtime version or commit: 4834727

Operating system: Ubuntu 25.10

Architecture: x86_64

Extra Info

Backtrace (not attached, sorry) mentions debug_tags from commit above

view this post on Zulip Wasmtime GitHub notifications bot (Mar 20 2026 at 06:17):

alexcrichton added the wasmtime:debugging label to Issue #12808.

view this post on Zulip Wasmtime GitHub notifications bot (Mar 20 2026 at 06:37):

Destructor17 edited issue #12808:

Test Case

main.wasm.gz

Steps to Reproduce

let engine = wasmtime::Engine::new(wasmtime::Config::new().guest_debug(true)).unwrap();
wasmtime::Module::from_file(&engine, "path/to/main.wasm").unwrap();

Expected Results

Module compiles successfully

Actual Results

An assertion failed

thread '<unnamed>' (62495) panicked at external/wasmtime/crates/cranelift/src/translate/stack.rs:548:9:
assertion failed: self.stack_shape.is_empty() || self.stack_shape.len() == self.stack.len()

Versions and Environment

Wasmtime version or commit: 4834727

Operating system: Ubuntu 25.10

Architecture: x86_64

view this post on Zulip Wasmtime GitHub notifications bot (Mar 21 2026 at 15:19):

alexcrichton closed issue #12808:

Test Case

main.wasm.gz

Steps to Reproduce

let engine = wasmtime::Engine::new(wasmtime::Config::new().guest_debug(true)).unwrap();
wasmtime::Module::from_file(&engine, "path/to/main.wasm").unwrap();

Expected Results

Module compiles successfully

Actual Results

An assertion failed

thread '<unnamed>' (62495) panicked at external/wasmtime/crates/cranelift/src/translate/stack.rs:548:9:
assertion failed: self.stack_shape.is_empty() || self.stack_shape.len() == self.stack.len()

Versions and Environment

Wasmtime version or commit: 4834727

Operating system: Ubuntu 25.10

Architecture: x86_64

Last updated: Mar 23 2026 at 16:19 UTC