| Index: src/wasm/module-decoder.cc
 | 
| diff --git a/src/wasm/module-decoder.cc b/src/wasm/module-decoder.cc
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| index 38402aef767e211ec4d7e2a8e46bfc8e969ad6be..062fe5b131792266c2f7c57b3a2f58757e4656a1 100644
 | 
| --- a/src/wasm/module-decoder.cc
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| +++ b/src/wasm/module-decoder.cc
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| @@ -475,7 +475,12 @@ class ModuleDecoder : public Decoder {
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|            case kExternalGlobal: {
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|              WasmGlobal* global = nullptr;
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|              exp->index = consume_global_index(module, &global);
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| -            if (global) global->exported = true;
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| +            if (global) {
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| +              if (global->mutability) {
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| +                error("mutable globals cannot be exported");
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| +              }
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| +              global->exported = true;
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| +            }
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|              break;
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|            }
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|            default:
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| 
 |