Installation output for pledge [fail]

Installation time: 0s

'/usr/home/chicken/salmonella/build/salmonella-run-publish/chicken/bin/chicken-install' -prefix /usr/home/chicken/salmonella/build/salmonella-run-publish/salmonella-repo/repo 2>&1


Error: extension is not targeted for this system: "pledge"
retrieving ...
checking platform for `pledge' ...