I'm using Keil tools. I get following link errors:
.\Builds\Octopus47.axf: Error: L6218E: Undefined symbol __debug__ (referred from at_ip.o). .\Builds\Octopus47.axf: Error: L6218E: Undefined symbol __error__ (referred from at_ip.o).
How can they be resolved? Is _ip.o Keil's TCP Stack library file?
Do you need to be linking in debug libraries, or not, to resolve the issue? If you're making a release build make sure not to include debug libraries, or defines that would enable debug features that the rest of the code are not supporting.