I have created a mod that renders some debug information in-game without the clutter of the whole debug screen, looks like this.

It works perfectly fine when the client is run from inside the IDE. However, once I compile the mod and run it through the Minecraft Launcher, it gives me this error upon loading up a world. https://gist.github.com/BovvzeR11/6acbae432779f5e1c929

 

I get no errors from the IDE and the field debug exists when looking through the Minecraft class source.

 

This is the code that I am using to get the Minecraft instance and the debug field. Full mod code here.

 

	private Minecraft mc;

public OverlayGui()
{
            super();
            mc = FMLClientHandler.instance().getClient();
}

@SubscribeEvent(priority = EventPriority.NORMAL)
public void renderFPSCU(RenderGameOverlayEvent event)
{
//...
            String debugString = this.mc.debug;
//...
        }

 

EDIT: Forgot to add, using Minecraft version 1.7.10, Forge 10.13.0.1152.

I was using the gradle build task, but it looks as though I have been grabbing the compiled version from the wrong place. Using the jar in \build\libs\ resolved the issue.