GHC has to walk a tight line between A) applying enough optimization passes to reliably remove abstraction overhead and B) compiling fast enough that people won

GHC has to walk a tight line between A) applying enough optimization passes to reliably remove abstraction overhead and B) compiling fast enough that people won't complain about it. It's pretty awesome what GHC can pull off in terms of reducing complex programs to a minimal normal form (you can see this with e.g. https://hackage.haskell.org/package/ghc-proofs-0.1.1/docs/GHC-Proof.html https://hackage.haskell.org/package/ghc-proofs-0.1.1/docs/GH... ), but often times you do have to convince the optimizer to be more aggressive than it wants to be.