At some point I'd actually like to explore trying to build a satisfactory "integer-fancy" in Haskell, but there's a few technical challenges I'll be trying to do first before there'll be an engineering story for building a satisfactory Haskell replacement that is performant enough to justify dropping Gmp
Basically I think until we can build an alternative with competitive performance in straight ghc Haskell, there's no good argument for dropping Gmp overall. There are a number of great reasons that everyone has mentioned, but it needs to be a net win for everyone before the leap could be justifiable.
If I manage to get my target work for 7.10 sorted out with a few months to spare, I may try to spend a few months exploring this, though no promises. Current ghc doesn't have the right primops to do this yet.
On Tuesday, October 22, 2013, Edward Kmett wrote:
Not suggesting we actually switch, but there is one strong 'why': You can't link Haskell code with any library that uses GMP internally internally without switching to using integer-simple. I've been trying with very limited success to get good MPFR bindings for Haskell for ~3 years now as a result.
The most likely fix actually involves changes to MPFR as their constant cache and our garbage collector don't play nice.