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`Store::wasm_fault` asserted that only one instance claims the faulting address. Importing a shared memory through `SharedMemory::vmimport` creates a single-memory instance that defines the same memory, so a fault in it was claimed twice and hit the assert instead of trapping. Only panic now when the address belongs to two different memories. Fixes bytecodealliance#14584
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Fixes #14584.
Store::wasm_faultasserts that only one instance in the store claims the faulting address. That doesn't hold for shared memories: importing one goes throughSharedMemory::vmimport, which creates a single-memory instance that defines the same memory. So in the example from the issue, both$aand that instance report the fault, and the assert fires instead of the trap.This keeps the check but only panics when the address belongs to two different memories, by comparing the
wasm_addresseach instance reports. It doesn't comparememory_size, since a shared memory can be grown by another thread between the two reads.I added the example from the issue as
tests/misc_testsuite/threads/shared-memory-imported-oob.wast. It panics atstore.rs:2061on main and passes with this change.cargo test --test wast,cargo test --test all -- shared_memory threads trapsandcargo test -p wasmtime --libpass locally on macOS (aarch64).I used Claude Code to reproduce the bug and test the fix locally.