Stream: git-wasmtime

Topic: wasmtime / PR #13616 [gc_fuzz]: Add concrete struct types...

Wasmtime GitHub notifications bot (Jun 12 2026 at 01:08):

khagankhan opened PR #13616 from khagankhan:concrete-struct-types to bytecodealliance:main:

References between struct types

• Concrete struct references — fields of type (ref null $t) pointing at any
  defined struct type, including self-references and cross-type cycles.

• Abstract structref fields — fields of type (ref null struct).

• Rec-group cycle merging — cross-group reference/supertype cycles are
  resolved by merging the strongly-connected rec groups into one (preserving all
  subtyping), instead of dropping supertype edges.

Scope / notes

• All references are nullable. Non-nullable references are deferred to a
  follow-up: a cycle of non-nullable references is uninhabitable, and detecting
  and repairing that in fixup is its own piece of work.

• Fixup degrades dangling concrete references to abstract structref and forces
  nullability, so every generated type stays constructible and valid.

• Bumped the default generation limits off zero so the fuzzer starts from a
  non-degenerate module.

+cc @fitzgen @eeide

Wasmtime GitHub notifications bot (Jun 12 2026 at 01:08):

khagankhan requested fitzgen for a review on PR #13616.

Wasmtime GitHub notifications bot (Jun 12 2026 at 01:08):

khagankhan requested wasmtime-fuzz-reviewers for a review on PR #13616.

Wasmtime GitHub notifications bot (Jun 12 2026 at 02:35):

github-actions[bot] added the label fuzzing on PR #13616.

Wasmtime GitHub notifications bot (Jun 12 2026 at 02:36):

github-actions[bot] commented on PR #13616:

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Wasmtime GitHub notifications bot (Jun 15 2026 at 19:03):

:thumbs_up: fitzgen submitted PR review:

Thanks!

Wasmtime GitHub notifications bot (Jun 15 2026 at 19:03):

fitzgen added PR #13616 [gc_fuzz]: Add concrete struct types as fields (nullable) to the merge queue

Wasmtime GitHub notifications bot (Jun 15 2026 at 19:29):

:check: fitzgen merged PR #13616.

Wasmtime GitHub notifications bot (Jun 15 2026 at 19:30):

fitzgen removed PR #13616 [gc_fuzz]: Add concrete struct types as fields (nullable) from the merge queue

Last updated: Jul 29 2026 at 05:03 UTC