executable ex9
  import: shared-properties
  main-is: src/ex/ex9.hs
  cxx-sources: src/ex/ex9.cpp

{snip}

if I edit the file: `src/ex/ex9.cpp`, and then execute: `cabal build`, I'm told:

$ cabal build
Up to date

Is this a known issue?

Is there a workaround?

Thanks,

-db