How can I highlight the warning and error lines in the make output?

Have a look at colormake, found here

$ apt-cache search colormake
colormake - simple wrapper around make to colorize output

Using the power of google, I also found this bash-function.

make()
{
  pathpat="(/[^/]*)+:[0-9]+"
  ccred=$(echo -e "\033[0;31m")
  ccyellow=$(echo -e "\033[0;33m")
  ccend=$(echo -e "\033[0m")
  /usr/bin/make "$@" 2>&1 | sed -E -e "/[Ee]rror[: ]/ s%$pathpat%$ccred&$ccend%g" -e "/[Ww]arning[: ]/ s%$pathpat%$ccyellow&$ccend%g"
  return ${PIPESTATUS[0]}
}