[Pkg-haskell-maintainers] Bug#640742: haskell-language-javascript: FTBFS: Grammar5.y: invalid character

[Aaron M. Ucko]

Source: haskell-language-javascript
Version: 0.4.5-2
Severity: serious
Justification: fails to build from source

Builds of haskell-language-javascript have been failing:

debian/hlibrary.setup build --builddir=dist-ghc
Preprocessing library language-javascript-0.4.5...
happy: src/Language/JavaScript/Parser/Grammar5.y: hGetContents: invalid argument (Invalid or incomplete multibyte or wide character)
make: *** [build-ghc-stamp] Error 1

Could you please take a look and ensure that that (e.g.) you set
locale-related variables appropriately?

Thanks!