IndexOutOfRangeException only on Mac OS X Standalone

I'm getting an IndexOutOfRange exception in my game, but only in a standalone build on Mac OS X. It works fine in the Unity editor on both Windows and OSX, and works fine as a standalone on Windows and Android. On OSX however, I get the following exception:

 IndexOutOfRangeException: Array index is out of range.
   at WorldController.InstantiateChunk (Vector2i pos, .MeshBuildInfo[] meshes) [0x00072] in /Users/sargunster/Code/Unity Projects/block-game/Assets/Scripts/World/Objects/WorldController.cs:226 
   at WorldController.FixedUpdate () [0x00060] in /Users/sargunster/Code/Unity Projects/block-game/Assets/Scripts/World/Objects/WorldController.cs:79 

Here's the relevant function:

 void InstantiateChunk(Vector2i pos, MeshBuildInfo[] meshes)
 {
     float worldX = pos.x * World.CHUNK_SIZE - .5f;
     float worldZ = pos.z * World.CHUNK_SIZE - .5f;

     // for each chunk in the column
     for (int y = 0; y < World.WORLD_HEIGHT; y++)
     {
         float worldY = y * World.CHUNK_SIZE - .5f;

         // instantiate the chunk
         Vector3 position = new Vector3(worldX, worldY, worldZ);
         string name = System.String.Format(" Chunk at ({0}, {1}, {2})", pos.x, y, pos.z);
         
         // THIS IS WHERE IT HAPPENED
         ChunkRenderer opaque = MakeChunk(position, "Opaque" + name, meshes[y].opaque, opaqueMaterial);
         
         ChunkRenderer transparent = MakeChunk(position, "Transparent" + name, meshes[y].transparent, transparentMaterial);
         Vector3i chunkPos = new Vector3i(pos.x, y, pos.z);
         opaqueInstances.Add(chunkPos, opaque);
         transparentInstances.Add(chunkPos, transparent);
     }
 }

I followed the references to find where meshes was instantiated, and it should have a length of WORLD_HEIGHT.

 MeshBuildInfo[] meshes = new MeshBuildInfo[World.WORLD_HEIGHT];

So, I went in to the debugger to see the exact value of the variable when the exception happened. Debugger output:

 > meshes
 Evaluation failed.
 > 2+2
 4
 > meshes.Length
 Evaluation failed.
 > y
 0
 > position
 {(-7168.5, -0.5, 4079.5)}

The index is 0, I can evaluation expressions just fine... except for the array that's not working. I can't get the length of it or its value.

I don't know how to solve this issue. What does "Evaluation Failed" mean? How can the index be out of bounds? Why is this only happening on OSX? How do I fix it?

World.WORLD_HEIGHT is a constant with a value of 16.