toOpenApi api never finishes compilation, split up version does

[KasperJanssens]

Hello,

I created an Api in servant and tried to get the servant-openapi3 library to generate openapi json from it. The api has 13 resources so it's not extremely large but I notice that the openapi generation hangs or at least takes a really really long time to finish ( let it run for over two hours and it still did not finish). When I split up the api in smaller subapis, of about max four resources and paste them back together in an overarching api compilation finishes in a matter of seconds.

I created a test project, using stack, ghc 8.10.4, most of the other versions and infos can likely be discerned from the repo, if not just ask and I will provide.

In that test project you can find two files, the TestApiSplitUp which finishes compilation and the TestApi which does not. Commenting out the toOpenApi statement makes the compilation finish so fairly sure that is the issue.

Kasper

[jumper149]

A solution that works for me, is by moving the toOpenApi call into a separate module and to that module I added:

{-# OPTIONS_GHC -O0 #-}

This way I didn't have to touch the actual API.