Fix for issue 25236

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "vm/class_finalizer.h"
@@ skipping 1293 matching lines @@
 }
 
 
 DART_EXPORT void Dart_EnterIsolate(Dart_Isolate isolate) {
   CHECK_NO_ISOLATE(Isolate::Current());
   // TODO(16615): Validate isolate parameter.
   Isolate* iso = reinterpret_cast<Isolate*>(isolate);
   if (iso->HasMutatorThread()) {
     FATAL("Multiple mutators within one isolate is not supported.");
   }
-  Thread::EnterIsolate(iso);
+  if (!Thread::EnterIsolate(iso)) {
+    FATAL("Unable to Enter Isolate as Dart VM is shutting down");
+  }
 }
 
 
 DART_EXPORT void Dart_ThreadDisableProfiling() {
   OSThread* os_thread = OSThread::Current();
   if (os_thread == NULL) {
     return;
   }
   os_thread->DisableThreadInterrupts();
 }
@@ skipping 195 matching lines @@
     Thread::ExitIsolate();
     RunLoopData data;
     data.monitor = &monitor;
     data.done = false;
     I->message_handler()->Run(
         Dart::thread_pool(),
         NULL, RunLoopDone, reinterpret_cast<uword>(&data));
     while (!data.done) {
       ml.Wait();
     }
-    Thread::EnterIsolate(I);
+    if (!Thread::EnterIsolate(I)) {
+      FATAL("Inconsistent state, VM shutting down while in run loop.");
+    }
   }
   if (I->object_store()->sticky_error() != Object::null()) {
     Dart_Handle error = Api::NewHandle(T, I->object_store()->sticky_error());
     I->object_store()->clear_sticky_error();
     return error;
   }
   if (FLAG_print_class_table) {
     HANDLESCOPE(T);
     I->class_table()->Print();
   }
@@ skipping 4423 matching lines @@
                                    ApiReallocate);
   writer.WriteFullSnapshot();
   *vm_isolate_snapshot_size = writer.VmIsolateSnapshotSize();
   *isolate_snapshot_size = writer.IsolateSnapshotSize();
   *instructions_snapshot_size = writer.InstructionsSnapshotSize();
 
   return Api::Success();
 }
 
 }  // namespace dart