Document that Isolate::GetCurrent() must not be called before initialization

src/isolate.cc

 // Copyright 2012 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 <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
 
 #include "src/v8.h"
@@ skipping 100 matching lines @@
   while (promise_on_stack_) isolate_->PopPromise();
 }
 
 
 base::Thread::LocalStorageKey Isolate::isolate_key_;
 base::Thread::LocalStorageKey Isolate::thread_id_key_;
 base::Thread::LocalStorageKey Isolate::per_isolate_thread_data_key_;
 base::LazyMutex Isolate::thread_data_table_mutex_ = LAZY_MUTEX_INITIALIZER;
 Isolate::ThreadDataTable* Isolate::thread_data_table_ = NULL;
 base::Atomic32 Isolate::isolate_counter_ = 0;
+#if DEBUG
+base::Atomic32 Isolate::isolate_key_created_ = 0;
+#endif
 
 Isolate::PerIsolateThreadData*
     Isolate::FindOrAllocatePerThreadDataForThisThread() {
   ThreadId thread_id = ThreadId::Current();
   PerIsolateThreadData* per_thread = NULL;
   {
     base::LockGuard<base::Mutex> lock_guard(thread_data_table_mutex_.Pointer());
     per_thread = thread_data_table_->Lookup(this, thread_id);
     if (per_thread == NULL) {
       per_thread = new PerIsolateThreadData(this, thread_id);
@@ skipping 19 matching lines @@
     per_thread = thread_data_table_->Lookup(this, thread_id);
   }
   return per_thread;
 }
 
 
 void Isolate::InitializeOncePerProcess() {
   base::LockGuard<base::Mutex> lock_guard(thread_data_table_mutex_.Pointer());
   CHECK(thread_data_table_ == NULL);
   isolate_key_ = base::Thread::CreateThreadLocalKey();
+#if DEBUG
+  base::NoBarrier_Store(&isolate_key_created_, 1);
+#endif
   thread_id_key_ = base::Thread::CreateThreadLocalKey();
   per_isolate_thread_data_key_ = base::Thread::CreateThreadLocalKey();
   thread_data_table_ = new Isolate::ThreadDataTable();
 }
 
 
 Address Isolate::get_address_from_id(Isolate::AddressId id) {
   return isolate_addresses_[id];
 }
 
@@ skipping 2373 matching lines @@
   if (prev_ && prev_->Intercept(flag)) return true;
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 } }  // namespace v8::internal