Hi,

These are Gcc variables not maintained by the ide.

Maybe the arduino ide resets the __LINE__ and __FILE__ ? 

I will investigate.

Okay I have seen what is required. 

During the past 12 months Arduino has moved to a new build system. Visual Micro has done the same except for one outstanding job related to how function prototypes and the arduino.h header are automatically inserted into the temporary .cpp prior to build.

It turns out the same system adjusts the compilers __FILE__ and __LINE__ knowledge. It's a better way to work and removes the need to handle the switching of source locations in the compiler error output and debug handlers.

An update should be available within the next few weeks with the changes. I'll post here the version number when it is.

Arduino solution released and discussed here