Fix witty export of functions with 16 parameters second attempt #2530
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Instead of manually creating the very deeply nested type.
Use the new fork release which updates the version of `wat` so that there's no conflict with the new version of `wasmtime`.
Include the fix that allows usage of 17 parameters with typed exported functions.
Keep them as flat parameters instead, even if the return type needs to be lowered as well.
They were added to work-around the issue with function parameters that flattened to 16 flat types, and with the fix they are no longer needed.
afck
approved these changes
Sep 24, 2024
jvff
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Motivation
This is a second attempt to fix the issue, the first one (#2429) blocked publishing new crate versions because it depended on a fix that was upstreamed to
wasmtime, but hadn't been included in a release yet. To remove the blocker it was reverted (by #2435) but now the newly released version 25.0.0 ofwasmtimeincludes the fix that's needed.When exporting functions with a specific signature type (with parameters that are flattened to exactly 16 flat types and with a return type that flattens to more than one flat type) to a Wasm instance, Witty's
#[wit_export]macro would incorrectly lower all parameters and return types to the type.This is different from what was specified in the specification.
Proposal
Don't lower the parameters of functions if they can be flattened into 16 flat types, even if the return type is lowered into the heap.
Test Plan
Ran tests manually to ensure that the
test_memory_run_application_with_dependencypasses without the dummy parameter that was introduced previously as a workaround before this fix.Release Plan
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