`Config::wasm_bulk_memory(false)` cannot be usefully specified without enabling the `gc` feature.

[nagisa]

Test Case

N/A

Steps to Reproduce

1. Depend on wasmtime with the runtime feature, but without the gc feature;
2. Set Config::wasm_bulk_memory(false) (cannot set Config::wasm_reference_types);
3. Invoke the runtime.

Expected Results

The wasm_reference_types feature should be considered disabled (and/or it should be possible to disable the feature without enabling the entire gc feature.)

Actual Results

wasmtime returns Err(feature 'reference_types' requires 'bulk_memory' to be enabled)

Versions and Environment

Wasmtime version or commit: 26.0.1

Operating system: Linux

Architecture: x86_64

Extra Info

wasm_reference_types config was not hidden behind a feature in the past. I'm attempting to update wasmtime from 14.0.1.

REFERENCE_TYPES gets set by the default set of supported features via WasmFeatures::WASM2.

My suggestion here is that Config parameters perhaps should not be gated by crate features.

[alexcrichton]

Thanks for the report! I've updated this in #9623 to remove this now-unnecessary validation.

It's also perhaps worth noting that this is something where you may want to run wasmparser::validate ahead of time with a custom feature set if you're looking to turn off some features. That way you can be sure to disable reference-types even when the gc feature is disabled (as otherwise it'll always be enabled, it's just gc types that are disabled)

[nagisa]

Cool, yeah that would work for me as I'm already validating with wasmparser first.