Fix leakage of virtual address space on Linux platform.

src/spaces.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 323 matching lines @@
 
   if (executable == EXECUTABLE) {
     ASSERT(size_executable_ >= size);
     size_executable_ -= size;
   }
   if (isolate_->code_range()->contains(static_cast<Address>(base))) {
     ASSERT(executable == EXECUTABLE);
     isolate_->code_range()->FreeRawMemory(base, size);
   } else {
     ASSERT(executable == NOT_EXECUTABLE || !isolate_->code_range()->exists());
-    VirtualMemory::ReleaseRegion(base, size);
+    bool result = VirtualMemory::ReleaseRegion(base, size);
+    USE(result);
+    ASSERT(result);
   }
 }
 
 
 Address MemoryAllocator::ReserveAlignedMemory(size_t size,
                                               size_t alignment,
                                               VirtualMemory* controller) {
   VirtualMemory reservation(size, alignment);
 
   if (!reservation.IsReserved()) return NULL;
@@ skipping 2158 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal