export CPPFLAGS="-I/Users/anders/gfan/cddlib/include"
./configure
make includedir=/Users/anders/gfan/cddlib/include

or

export CPPFLAGS="-I/home/ren/cddlib-094f/lib-src-gmp/"
./configure
make includedir=/home/ren/cddlib-094f/lib-src-gmp/