Use /usr/local as default PREFIX.
Use /usr/local as default PREFIX.

diku-dk/futhark,HIPERFIT/futhark,diku-dk/futhark,diku-dk/futhark,ihc/futhark,ihc/futhark,diku-dk/futhark,HIPERFIT/futhark,HIPERFIT/futhark,diku-dk/futhark,ihc/futhark