Stream: git-wasmtime

Topic: wasmtime / issue #14346 Link host-side interface with can...

Wasmtime GitHub notifications bot (Sep 16 2026 at 00:25):

chenyan2002 opened issue #14346:

When -W component-model-canonical-names feature is enabled, the guest side component encodes interface names with canonical names, while the host-side bindgen is still using the full version. This causes the linking to fail.

NameMap currently supports matching a:b/c@0.2.1 with its alternate key a:b/c@0.2. But if the component is importing a:b/c@0.2, we cannot match it back with a:b/c@0.2.1. We need to refactor NameMap/alternate_lookup_key to be able to handle both canonical version and full version during the transition period.

Another fix is to add an option in the host side wit-bindgen to emit canonical names. But when the component is importing a full version, NameMap needs to know how to match it with the canonical name.

Raised from https://github.com/bytecodealliance/wasmtime/pull/14344#discussion_r4019873593

Wasmtime GitHub notifications bot (Sep 16 2026 at 14:07):

alexcrichton added the wasm-proposal:component-model label to Issue #14346.

Wasmtime GitHub notifications bot (Sep 16 2026 at 14:19):

alexcrichton commented on issue #14346:

I haven't sat down to think through a full solution just yet, but the main property I think that should be upheld is that turning on and/or rolling out canonical names should not break any preexisting behaviors. For example turning on the CLI feature shouldn't cause any existing workflows to break. Additionally if this were a bindgen! feature then turning that on in wasmtime-wasi shouldn't cause any existing workflows to break. I think it's fine if the way this is configured opts-in to more behaviors or perhaps disallows some pretty edge-case-y behaviors but for big things like "instantiating a preexisting component using WASI not using canonical-names" should not break.

I'd probably personally lean towards not changing insertion into a linker and leave bindgen! dealing with full versions. Internally the NameMap would satisfy requests for 0.2 with 0.2.1 then, for example. I haven't fully thought this through, however.

Last updated: Sep 20 2026 at 18:08 UTC