The compiler is reporting the same set of warnings for multiple files due to conflicting errno definitions conditionally included via "#ifdef LWIP_PROVIDE_ERRNO" at line 77 of arch.h. The symbol appears for definition at line 161 of lwipopts.h and line 37 of cc.h - One definition and one commented out. No joy in attempting to build with a consistent definition (ie. defined in both header files or commented out in both headers).
Has this demo configuration been successfully built, and if so, how?