Fix assertion in br_on_cast finalization#8476
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kripken
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test/lit/validation/shared-cast.wast
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| (type $unshared (struct)) | ||
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| (func $shared-to-unshared (param $s (ref $shared)) | ||
| ;; CHECK: [wasm-validator error in function shared-to-unshared] unexpected false: unreachable instruction must have unreachable child |
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These messages are not clear as to the actual problem. Can the validator at least add "this can happen if [.. common case ..]"?
If the br_on_cast is invalid because its input and output types are unrelated, the GLB used as the new cast type will be unreachable. This caused an assertion that the GLB was a reference to fail. Bail out early in this case and leave the unreachable cast type for the validator to find.
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If the br_on_cast is invalid because its input and output types are unrelated, the GLB used as the new cast type will be unreachable. This caused an assertion that the GLB was a reference to fail. Bail out early in this case and leave the unreachable cast type for the validator to find.