Wasmtime GitHub notifications bot (Oct 16 2026 at 15:21): Wasmtime GitHub notifications bot (Oct 16 2026 at 15:21):alexcrichton opened PR #14782 from alexcrichton:refactor-globals to bytecodealliance:main:
This commit refactors the representation of
VMGlobalDefinitionwhich for the longest time has been[u8; 16]and IIRC predates the addition ofunionto Rust. The previous implementation had a bug wherefuncreffields were loaded/stored as*mut VMFuncRefbut this is not compatible with provenance and Pulley. Instead globals needed to useOption<VmPtr<VMFuncRef>>, and instead of just fixing this one case for globals I've refactored globals to use aunion.The change here reflects the internal representation of wasm globals and how Cranelift accesses them. Documentation is additionally added indicating that some fields are little-endian and some are native-endian. The field type for
funcrefisOption<VmPtr<_>>to resolve the provenance issue as well.<!--
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Wasmtime GitHub notifications bot (Oct 16 2026 at 15:21):alexcrichton requested fitzgen for a review on PR #14782.
Wasmtime GitHub notifications bot (Oct 16 2026 at 15:21):alexcrichton requested wasmtime-core-reviewers for a review on PR #14782.
Wasmtime GitHub notifications bot (Oct 16 2026 at 15:21):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #14782.
Wasmtime GitHub notifications bot (Oct 16 2026 at 15:56):alexcrichton updated PR #14782.
Wasmtime GitHub notifications bot (Oct 16 2026 at 17:45):github-actions[bot] added the label wasmtime:api on PR #14782.
Wasmtime GitHub notifications bot (Oct 16 2026 at 19:45)::thumbs_up: fitzgen submitted PR review:
Thanks!
Wasmtime GitHub notifications bot (Oct 16 2026 at 19:45)::speech_balloon: fitzgen created PR review comment:
I couldn't find a pre-existing issue on file for this TODO, mind creating one so it doesn't get lost?
Wasmtime GitHub notifications bot (Oct 16 2026 at 19:45)::speech_balloon: fitzgen created PR review comment:
Ah, nevermind, I see the TODO didn't get lost
Wasmtime GitHub notifications bot (Oct 16 2026 at 19:45):fitzgen added PR #14782 Represent globals as a proper union, fix provenance to the merge queue.
Wasmtime GitHub notifications bot (Oct 16 2026 at 20:09)::check: fitzgen merged PR #14782.
Wasmtime GitHub notifications bot (Oct 16 2026 at 20:09):fitzgen removed PR #14782 Represent globals as a proper union, fix provenance from the merge queue.
Last updated: Oct 31 2026 at 23:03 UTC