[wasm] Do not try start linking if the compilation failed.

src/wasm/wasm-module.cc

 // Copyright 2015 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.
 
 #include "src/base/atomic-utils.h"
 #include "src/macro-assembler.h"
 #include "src/objects.h"
 #include "src/property-descriptor.h"
 #include "src/v8.h"
 
@@ skipping 756 matching lines @@
       // 4) After the parallel phase of all compilation units has started, the
       //    main thread waits for all {WasmCompilationTask} instances to finish.
       WaitForCompilationTasks(isolate, task_ids.get(), pending_tasks);
       // Finish the compilation of the remaining compilation units.
       FinishCompilationUnits(executed_units, results, result_mutex);
     }
     // 5) The main thread finishes the compilation.
     if (!FinishCompilation(isolate, this, ffi, results, instance, code_table,
                            thrower, factory, module_env, code_stats, desc)) {
       instance.js_object = Handle<JSObject>::null();
+      return instance.js_object;
     }
 
     // Patch all direct call sites.
     linker.Link(instance.function_table, this->function_table);
     instance.js_object->SetInternalField(kWasmModuleFunctionTable,
                                          Smi::FromInt(0));
 
     //-------------------------------------------------------------------------
     // Create and populate the exports object.
     //-------------------------------------------------------------------------
@@ skipping 194 matching lines @@
                                         uint32_t func_index) {
   Object* func_names_arr_obj = wasm->GetInternalField(kWasmFunctionNamesArray);
   if (func_names_arr_obj->IsUndefined()) return Handle<String>::null();
   return GetWasmFunctionNameFromTable(
       handle(ByteArray::cast(func_names_arr_obj)), func_index);
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8