[wasm] Exporting i64 globals causes a link error.

test/mjsunit/wasm/globals.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --expose-wasm
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
 function TestImported(type, val, expected) {
@@ skipping 26 matching lines @@
   builder.addGlobal(kWasmI32);  // pad
 
   var instance = builder.instantiate();
   assertEquals(expected, instance.exports.foo);
 }
 
 TestExported(kWasmI32, 455.5, 455);
 TestExported(kWasmF32, -999.34343, Math.fround(-999.34343));
 TestExported(kWasmF64, 87347.66666, 87347.66666);
 
+(function TestI64Exported() {
+  var builder = new WasmModuleBuilder();
+  var sig = makeSig([kWasmI64], []);
+  builder.addGlobal(kWasmI32);  // pad
+  var g = builder.addGlobal(kWasmI64, false)
+      .exportAs("foo");
+  g.init = 1234;
+  builder.addGlobal(kWasmI32);  // pad
+
+  assertThrows(()=> {builder.instantiate()}, WebAssembly.LinkError);
+})();
 
 function TestImportedExported(type, val, expected) {
   print("TestImportedExported " + type + "(" + val +")" + " = " + expected);
   var builder = new WasmModuleBuilder();
   var sig = makeSig([type], []);
   var i = builder.addImportedGlobal("ttt", "foo", type);
   builder.addGlobal(kWasmI32);  // pad
   var o = builder.addGlobal(type, false)
       .exportAs("bar");
   o.init_index = i;
@@ skipping 21 matching lines @@
     .addBody([kExprGetGlobal, def.index])
     .exportAs("main");
 
   var instance = builder.instantiate({nnn: {foo: val}});
   assertEquals(val, instance.exports.main());
 }
 
 TestGlobalIndexSpace(kWasmI32, 123);
 TestGlobalIndexSpace(kWasmF32, 54321.125);
 TestGlobalIndexSpace(kWasmF64, 12345.678);