Stream: git-wasmtime

Topic: wasmtime / PR #15046 Remove `RuntimeMemoryCreator` and th...

Wasmtime GitHub notifications bot (Oct 28 2026 at 16:23):

V0ldek opened PR #15046 from V0ldek:v0ldek/remove-runtime-memory-creator to bytecodealliance:main:

As discussed in #14989, this PR flattens the memory creation path by making the internals use the same trait as the public API (MemoryCreator).

The biggest change is the public API change for MemoryCreator, where it now receives all parameters to new_memory packaged in MemoryRequest. This allows us to expose all the previous configuration parameters that implementations require for correctness, while hiding some internal tunables that are used in the DefaultMemoryCreator. The public API surface is slightly increased to include a MemoryKind enum that notifies the creator whether it's creating a standard linear memory or a GC heap, in case implementations want to serve these two differently. I also added docs for telling people how GC heaps differ from linear memory.

The actual code changes are mostly mechanical:

• the MemoryRequest exposes the parameters as public accessors, plus pub(crate) ones for the internal parameters
• RuntimeMemoryCreator trait is gone and everything that refered to it refers to MemoryCreator instead
• the MemoryCreatorProxy became dead code and was removed.

Added one test for the GC creation path to ensure we don't issue multiple heap requests to the creator once one was created for a store.

The C and C++ APIs were updated to match the signatures of Rust.

Wasmtime GitHub notifications bot (Oct 28 2026 at 16:23):

V0ldek removed the review request for wasmtime-core-reviewers from PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 16:23):

V0ldek requested fitzgen for a review on PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 16:23):

V0ldek requested wasmtime-core-reviewers for a review on PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 16:26):

V0ldek updated PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 18:44):

github-actions[bot] added the label wasmtime:config on PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 18:44):

github-actions[bot] added the label wasmtime:api on PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 18:44):

github-actions[bot] added the label wasmtime:c-api on PR #15046.

Wasmtime GitHub notifications bot (Oct 28 2026 at 19:45):

github-actions[bot] commented on PR #15046:

Label Messager: wasmtime:config

It looks like you are changing Wasmtime's configuration options. Make sure to
complete this check list:

• [ ] If you added a new Config method, you wrote extensive documentation for
  it.

  <details>

  Our documentation should be of the following form:

  ```text
  Short, simple summary sentence.

  More details. These details can be multiple paragraphs. There should be
  information about not just the method, but its parameters and results as
  well.

  Is this method fallible? If so, when can it return an error?

  Can this method panic? If so, when does it panic?

  Example

  Optional example here.
  ```

  </details>

• [ ] If you added a new Config method, or modified an existing one, you
  ensured that this configuration is exercised by the fuzz targets.

  <details>

  For example, if you expose a new strategy for allocating the next instance
  slot inside the pooling allocator, you should ensure that at least one of our
  fuzz targets exercises that new strategy.

  Often, all that is required of you is to ensure that there is a knob for this
  configuration option in [wasmtime_fuzzing::Config][fuzzing-config] (or one
  of its nested structs).

  Rarely, this may require authoring a new fuzz target to specifically test this
  configuration. See [our docs on fuzzing][fuzzing-docs] for more details.

  </details>

• [ ] If you are enabling a configuration option by default, make sure that it
  has been fuzzed for at least two weeks before turning it on by default.

[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

---

<details>

To modify this label's message, edit the <code>.github/label-messager/wasmtime-config.md</code> file.

To add new label messages or remove existing label messages, edit the
<code>.github/label-messager.json</code> configuration file.

Learn more.

</details>

Wasmtime GitHub notifications bot (Oct 29 2026 at 14:32):

:thumbs_up: alexcrichton submitted PR review:

Thanks for this!

Wasmtime GitHub notifications bot (Oct 29 2026 at 14:33):

alexcrichton added PR #15046 Remove RuntimeMemoryCreator and the proxy. to the merge queue

Wasmtime GitHub notifications bot (Oct 29 2026 at 18:21):

github-merge-queue[bot] removed PR #15046 Remove RuntimeMemoryCreator and the proxy. from the merge queue

Wasmtime GitHub notifications bot (Oct 29 2026 at 19:36):

alexcrichton added PR #15046 Remove RuntimeMemoryCreator and the proxy. to the merge queue

Wasmtime GitHub notifications bot (Oct 29 2026 at 23:43):

alexcrichton removed PR #15046 Remove RuntimeMemoryCreator and the proxy. from the merge queue

Wasmtime GitHub notifications bot (Oct 29 2026 at 23:43):

:check: alexcrichton merged PR #15046.

Last updated: Oct 31 2026 at 23:03 UTC