Mirage      Using scanned config file: config.ml
Mirage      Processing: /Users/dongcarl/src/mirage-skeleton/block/config.ml
Mirage      => rm -rf /Users/dongcarl/src/mirage-skeleton/block/_build/config.*
Mirage      => cd /Users/dongcarl/src/mirage-skeleton/block && ocamlbuild -use-ocamlfind -tags annot,bin_annot -pkg mirage config.cmxs
mirage: internal error, uncaught exception:
        File "config.ml", line 6, characters 4-9: Pattern matching failed