fix: handle NULL method in LMF during WASM exception unwinding#156
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jeromelaban merged 1 commit intomainfrom Apr 10, 2026
Merged
fix: handle NULL method in LMF during WASM exception unwinding#156jeromelaban merged 1 commit intomainfrom
jeromelaban merged 1 commit intomainfrom
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When hot reload applies metadata deltas across multiple generations, the LMF (Last Managed Frame) chain can contain entries with NULL method pointers — caused by partially initialized JIT frames during skeleton type creation or ALC unloading.
WASM is the only architecture that hard-asserts on (*lmf)->method (exceptions-wasm.c:66). x86 returns FALSE gracefully; AMD64/ARM64 don't depend on the method field at all.
- Add patch 0005 to Uno.DotnetRuntime.WebAssembly: skip NULL method LMF entries and return FALSE, matching x86 behavior
- Add WASM runtime test exercising multi-generation hot reload via MetadataUpdater.ApplyUpdate with Roslyn EmitDifference deltas
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When hot reload applies metadata deltas across multiple generations, the LMF (Last Managed Frame) chain can contain entries with NULL method pointers — caused by partially initialized JIT frames during skeleton type creation or ALC unloading.
WASM is the only architecture that hard-asserts on (*lmf)->method (exceptions-wasm.c:66). x86 returns FALSE gracefully; AMD64/ARM64 don't depend on the method field at all.