Is there any other error info? that post doesn't contain an error.
Why are you adding cc files to the headers listing? they're not headers.
Removing the target tells it to build nothing at all. It needs a target.
Questions about kdevelop rather than actual
programming may be better placed in the software forums. kdevelop's not the language or the compiler, it just uses them (badly).
Lastly, I don't reccomend kdevelop due to its
addiction to automake.