Fix the Cygwin build

test/cctest/test-alloc.cc

 // Copyright 2007-2008 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 182 matching lines @@
 
   while (total_allocated < 5 * code_range_size) {
     if (current_allocated < code_range_size / 10) {
       // Allocate a block.
       // Geometrically distributed sizes, greater than Page::kPageSize.
       size_t requested = (Page::kPageSize << (Pseudorandom() % 6)) +
            Pseudorandom() % 5000 + 1;
       size_t allocated = 0;
       void* base = Isolate::Current()->code_range()->
           AllocateRawMemory(requested, &allocated);
+      CHECK(base != NULL);
       blocks.Add(Block(base, static_cast<int>(allocated)));
       current_allocated += static_cast<int>(allocated);
       total_allocated += static_cast<int>(allocated);
     } else {
       // Free a block.
       int index = Pseudorandom() % blocks.length();
       Isolate::Current()->code_range()->FreeRawMemory(
           blocks[index].base, blocks[index].size);
       current_allocated -= blocks[index].size;
       if (index < blocks.length() - 1) {
         blocks[index] = blocks.RemoveLast();
       } else {
         blocks.RemoveLast();
       }
     }
   }
 
   Isolate::Current()->code_range()->TearDown();
 }