Check for class id overflow to exit rather than crash.

runtime/vm/class_table.cc

 // Copyright (c) 2012, 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 "vm/class_table.h"
 #include "vm/flags.h"
 #include "vm/freelist.h"
 #include "vm/heap.h"
 #include "vm/object.h"
 #include "vm/raw_object.h"
@@ skipping 71 matching lines @@
                   new_capacity * sizeof(ClassHeapStats)));  // NOLINT
       for (intptr_t i = capacity_; i < new_capacity; i++) {
         new_table[i] = NULL;
         new_stats_table[i].Initialize();
       }
       capacity_ = new_capacity;
       table_ = new_table;
       class_heap_stats_table_ = new_stats_table;
     }
     ASSERT(top_ < capacity_);
+    if (!Class::is_valid_id(top_)) {
+      FATAL1("Fatal error in ClassTable::Register: invalid index %" Pd "\n",

[Ivan Posva, 2014/04/18 16:39:27]

FATAL is OK for now, but we really should just throw an error in this isolate.
There is no reason to kill the process in general.

+             top_);
+    }
     cls.set_id(top_);
     table_[top_] = cls.raw();
     top_++;  // Increment next index.
   }
 }
 
 
 void ClassTable::RegisterAt(intptr_t index, const Class& cls) {
   ASSERT(index != kIllegalCid);
   ASSERT(index >= kNumPredefinedCids);
   if (index >= capacity_) {
     // Grow the capacity of the class table.
     intptr_t new_capacity = index + capacity_increment_;
-    if (new_capacity < capacity_) {
+    if (!Class::is_valid_id(index) || new_capacity < capacity_) {
       FATAL1("Fatal error in ClassTable::Register: invalid index %" Pd "\n",
              index);
     }
     RawClass** new_table = reinterpret_cast<RawClass**>(
         realloc(table_, new_capacity * sizeof(RawClass*)));  // NOLINT
     ClassHeapStats* new_stats_table = reinterpret_cast<ClassHeapStats*>(
         realloc(class_heap_stats_table_,
                 new_capacity * sizeof(ClassHeapStats)));  // NOLINT
     for (intptr_t i = capacity_; i < new_capacity; i++) {
       new_table[i] = NULL;
@@ skipping 310 matching lines @@
 
 void ClassTable::UpdateLiveNew(intptr_t cid, intptr_t size) {
   ClassHeapStats* stats = StatsAt(cid);
   ASSERT(stats != NULL);
   ASSERT(size >= 0);
   stats->post_gc.AddNew(size);
 }
 
 
 }  // namespace dart