Stream: git-wasmtime

Topic: wasmtime / PR #14801 Enable the component model map featu...

Wasmtime GitHub notifications bot (Oct 19 2026 at 06:29):

jrandolf opened PR #14801 from jrandolf:cm-map-default to bytecodealliance:main:

WASI 0.3.1 adopted the map<K, V> type, which means runtimes need to support it to be compatible with WASI 0.3.1 and later (see ComponentModelFeatures.md). docs/stability-wasm-proposals.md already lists every criterion as met for map, so this flips the default and moves it into the on-by-default table.

Without this a component that uses map fails to load unless -W component-model-map is passed.

Wasmtime GitHub notifications bot (Oct 19 2026 at 06:29):

jrandolf requested dicej for a review on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 06:29):

jrandolf requested wasmtime-core-reviewers for a review on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 06:29):

jrandolf requested fitzgen for a review on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 06:29):

jrandolf requested wasmtime-default-reviewers for a review on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 08:56):

github-actions[bot] added the label wasmtime:api on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 08:56):

github-actions[bot] added the label wasmtime:config on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 08:56):

github-actions[bot] added the label wasmtime:docs on PR #14801.

Wasmtime GitHub notifications bot (Oct 19 2026 at 09:54):

github-actions[bot] commented on PR #14801:

Label Messager: wasmtime:config

It looks like you are changing Wasmtime's configuration options. Make sure to
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[fuzzing-config]: https://github.com/bytecodealliance/wasmtime/blob/ca0e8d0a1d8cefc0496dba2f77a670571d8fdcab/crates/fuzzing/src/generators.rs#L182-L194
[fuzzing-docs]: https://docs.wasmtime.dev/contributing-fuzzing.html

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Wasmtime GitHub notifications bot (Oct 19 2026 at 15:50):

:thumbs_up: dicej submitted PR review.

Wasmtime GitHub notifications bot (Oct 19 2026 at 15:51):

:repeat: alexcrichton submitted PR review:

I don't believe that map<K, V> is suitable to enable just yet. I've filed a few issues:

• https://github.com/bytecodealliance/wasmtime/issues/14813
• https://github.com/bytecodealliance/wasmtime/issues/14812
• https://github.com/bytecodealliance/wasmtime/issues/14811
• https://github.com/bytecodealliance/wasmtime/issues/14810

These are the most serious issues I found in a review locally, but tehre's a litany of possible issues with bindgen! as well in terms of no-std compat, the limitations placed on the current impls, the lack of support for types in the current impls (e.g. no BTreeMap, no "just give me the list", etc).

Overall I do not personally feel that this is ready to just turn it on.

Wasmtime GitHub notifications bot (Oct 19 2026 at 18:23):

jrandolf commented on PR #14801:

Thanks for the review. Let me do some investigation and come back to you. I'll open some stabilization PRs.

Wasmtime GitHub notifications bot (Oct 19 2026 at 18:24):

jrandolf edited a comment on PR #14801:

Thanks for the review. Let me do some investigation and come back to you. I'll open some PRs toward stabilization

Wasmtime GitHub notifications bot (Oct 20 2026 at 00:34):

jrandolf updated PR #14801.

Wasmtime GitHub notifications bot (Oct 21 2026 at 18:22):

fitzgen removed the review request for fitzgen from PR #14801.

Wasmtime GitHub notifications bot (Oct 21 2026 at 18:28):

jrandolf updated PR #14801.

Last updated: Oct 31 2026 at 23:03 UTC