Report syntax errors in natives when building with mksnapshot.

src/mksnapshot.cc

 // Copyright 2006-2008 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 284 matching lines @@
   }
 #ifdef COMPRESS_STARTUP_DATA_BZ2
   BZip2Decompressor natives_decompressor;
   int bz2_result = natives_decompressor.Decompress();
   if (bz2_result != BZ_OK) {
     fprintf(stderr, "bzip error code: %d\n", bz2_result);
     exit(1);
   }
 #endif
   i::Serializer::Enable();
+  TryCatch try_catch(NULL);
   Persistent<Context> context = v8::Context::New();
+  if (try_catch.HasCaught()) {
+    fprintf(stderr,
+            "\nException thrown while compiling natives - see above.\n\n");
+    exit(1);
+  }
   ASSERT(!context.IsEmpty());
   // Make sure all builtin scripts are cached.
   { HandleScope scope;
     for (int i = 0; i < i::Natives::GetBuiltinsCount(); i++) {
       i::Isolate::Current()->bootstrapper()->NativesSourceLookup(i);
     }
   }
   // If we don't do this then we end up with a stray root pointing at the
   // context even after we have disposed of the context.
   HEAP->CollectAllGarbage(i::Heap::kNoGCFlags, "mksnapshot");
@@ skipping 23 matching lines @@
   sink.WriteSpaceUsed(
       partial_ser.CurrentAllocationAddress(i::NEW_SPACE),
       partial_ser.CurrentAllocationAddress(i::OLD_POINTER_SPACE),
       partial_ser.CurrentAllocationAddress(i::OLD_DATA_SPACE),
       partial_ser.CurrentAllocationAddress(i::CODE_SPACE),
       partial_ser.CurrentAllocationAddress(i::MAP_SPACE),
       partial_ser.CurrentAllocationAddress(i::CELL_SPACE),
       partial_ser.CurrentAllocationAddress(i::LO_SPACE));
   return 0;
 }