Maybe. It's a type error. The -1 can't go into an unsigned type, because the "-" is the sign.

I'm afraid to be sure you're doing it right, you have to understand the surrounding code.

But possible fixes include:

• Changing -1 to an unsigned number.

• Changing the type of the variable it goes into.

• Something entirely different, maybe even deleting that part of the code.

Did you modify the make file? By what I understood from the source code, the -1 is a separator for differente escape codes

The make file defines if it's ok to implicitly convert -1 to an unsigned integer (note the -W narrowing flag in red).