Very slow (8min w/ minimal exts, 18min with GHC2021) to typecheck reasonably-sized Happy grammar
I have a reasonably-sized (about 200 lines of grammar, about 130 lines of support code) Happy grammar that takes a whopping 18 minutes to build under GHC 9.0.1, when the extensions present in GHC2021 are in Cabal's
default-extensions. It's down to 8 minutes when pared down to a minimal set. Passing
-ddump-timings shows almost all the time being spent in typechecking.
The generated code is here.
Steps to reproduce
git clone https://git.sr.ht/~remexre/sylvan
- Note the very long build times for
Compile in not more than 2-3 minutes. (At least, not more than the rest of the project put together!)
- GHC version used: 9.0.1
- Operating System: Linux (NixOS)
- System Architecture: x86_64