[WIP] Update HPC for better compatibility with large projects

[peterbecich]

With large projects HPC can produce an argument list too long error: https://github.com/NixOS/nix/issues/5593

This can be avoided by passing arguments to HPC as Response Files: https://gcc.gnu.org/wiki/Response_Files

Needs https://gitlab.haskell.org/ghc/ghc/-/merge_requests/8194 and a new release of HPC to Hackage

Follows https://github.com/input-output-hk/haskell.nix/pull/1464 (see https://github.com/input-output-hk/haskell.nix/pull/1464#issuecomment-1122123517)

[michaelpj]

Thanks for pursuing this upstream! Future users will thank you :)

[peterbecich]

https://gitlab.haskell.org/ghc/ghc/-/merge_requests/8194 has been merged

[michaelpj]

Nice work! I guess we still either need to pull in the patch or else make the coverage code conditional since otherwise it will stop working for older GHCs?

[hamishmack]

I have merged the latest changes from master and refactored the code so that it puts all the args in a single response file. I also reenabled two of the tests that had been disabled and updated them for changes that were made on master.

For now I have included the patch as a ghc patch, but we can potentially drop that if/when hpc is updated in hackage.

You can test pandoc and other hackage packages with:

nix-build -E '((import ./. {}).pkgs-unstable.haskell-nix.hackage-project { compiler-nix-name = "ghc8107"; name = "pandoc"; modules = [{doCoverage = true;}]; }).projectCoverageReport'

[hamishmack]

bors try

[iohk-bors[bot]]

try

Timed out.

[hamishmack]

bors try

[hamishmack]

bors try

[iohk-bors[bot]]

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Already running a review

[hamishmack]

bors try-

[hamishmack]

bors try

[iohk-bors[bot]]

try

Build failed:

• buildkite/haskell-dot-nix

[hamishmack]

bors try-

[hamishmack]

bors try

[iohk-bors[bot]]

try

Build succeeded:

• ci/hydra:Cardano:haskell-nix:required
• buildkite/haskell-dot-nix

[hamishmack]

I'm going to merge this because code coverage seems pretty broken in master and this at least works for the smaller projects I have tests.

I am worried that we removed this. Unfortunately every time I try to build ouroboros-network to test this issue I get bogged down by the zfs issue (cannot execute binary file: Exec format error).