inspection-testing fails to build with GHC 8.10.5

[jkachmar]

inspection-testing fails to build with haskell.nix when using GHC 8.10.5 and 8.10.4; it succeeds when building normally (cf. the inspection-testing CI).

I've verified that this happens with GHC 8.10.5 on the latest haskell.nix 21.05 and unstable nixpkgs pins.

To reproduce the failure, clone https://github.com/jkachmar/haskell-nix-inspection-testing-bug and build it with nix build . on a system that supports Nix Flakes.

You should encounter the following error:

GHC 8.10.5 error

error: builder for '/nix/store/fk4dhplcpqgp88kj09zisan54179rxq8-inspection-testing-lib-inspection-testing-0.4.5.0.drv' failed with exit code 1;
       last 10 log lines:
       >     |
       > 224 |     go_tick :: RnEnv2 -> Tickish Id -> Tickish Id -> Bool
       >     |                          ^^^^^^^
       > 
       > src/Test/Inspection/Core.hs:224:40: error:
       >     Not in scope: type constructor or class ‘Tickish’
       >     |
       > 224 |     go_tick :: RnEnv2 -> Tickish Id -> Tickish Id -> Bool
       >     |                                        ^^^^^^^
       > 

---

My only thought is that this is triggered by the unboxed tuples patch being applied to GHC 8.10.5, since Tickish is exported by CoreSyn prior to GHC 9.0.1 and it looks like there's quite a bit of mucking around going on there.

cf. https://github.com/input-output-hk/haskell.nix/blob/a5b74bf002bee3ee41012c8f5e48105150892eee/overlays/patches/ghc/ghc-8.10.5-ubxt.patch

---

Curiously it also seems to fail when compiling with GHC 9.0.1 using the unstable nixpkgs pin, but with a completely different error.

GHC 9.0.1 error

error: builder for '/nix/store/2npb1yxswm2pn9fkw2ryqw5zqwsh2s99-inspection-testing-lib-inspection-testing-0.4.5.0.drv' failed with exit code 1;
       last 10 log lines:
       > configuring
       > Configure flags:
       > --prefix=/nix/store/44pld05ryhd70jz9vdsmb56smx0dnira-inspection-testing-lib-inspection-testing-0.4.5.0 lib:inspection-testing --package-db=clear --package-db=/nix/store/7m5zlvn3350f15sp9z5lml2h9sx0gmww-inspection-testing-lib-inspection-testing-0.4.5.0-config/lib/ghc-9.0.1/package.conf.d --flags=-more-tests --flags=-old-text-tests --exact-configuration --dependency=rts=rts --dependency=ghc-heap=ghc-heap-9.0.1 --dependency=ghc-prim=ghc-prim-0.7.0 --dependency=integer-gmp=integer-gmp-1.1 --dependency=base=base-4.15.0.0 --dependency=deepseq=deepseq-1.4.5.0 --dependency=array=array-0.5.4.0 --dependency=ghc-boot-th=ghc-boot-th-9.0.1 --dependency=pretty=pretty-1.1.3.6 --dependency=template-haskell=template-haskell-2.17.0.0 --dependency=ghc-bignum=ghc-bignum-1.0 --dependency=ghc-boot=ghc-boot-9.0.1 --dependency=ghc=ghc-9.0.1 --dependency=Cabal=Cabal-3.4.0.0 --dependency=array=array-0.5.4.0 --dependency=binary=binary-0.8.8.0 --dependency=bytestring=bytestring-0.10.12.1 --dependency=containers=containers-0.6.4.1 --dependency=directory=directory-1.3.6.1 --dependency=filepath=filepath-1.4.2.1 --dependency=ghc-boot=ghc-boot-9.0.1 --dependency=ghc-compact=ghc-compact-0.1.0.0 --dependency=ghc-prim=ghc-prim-0.7.0 --dependency=hpc=hpc-0.6.1.0 --dependency=mtl=mtl-2.2.2 --dependency=parsec=parsec-3.1.14.0 --dependency=process=process-1.6.11.0 --dependency=text=text-1.2.4.1 --dependency=time=time-1.9.3 --dependency=transformers=transformers-0.5.6.2 --dependency=unix=unix-2.7.2.2 --dependency=xhtml=xhtml-3000.2.2.1 --dependency=terminfo=terminfo-0.4.1.4 --with-ghc=ghc --with-ghc-pkg=ghc-pkg --with-hsc2hs=hsc2hs --with-gcc=cc --with-ld=ld.gold --ghc-option=-optl-fuse-ld=gold --ld-option=-fuse-ld=gold --with-ar=ar --with-strip=strip --disable-executable-stripping --disable-library-stripping --disable-library-profiling --disable-executable-profiling --enable-static --enable-shared --disable-coverage --enable-library-for-ghci --enable-split-sections
       > Configuring library for inspection-testing-0.4.5.0..
       > Warning: The flag --disable-executable-profiling is deprecated. Please use
       > --disable-profiling instead.
       > Error:
       >     The following packages are broken because other packages they depend on are missing. These broken packages must be rebuilt before they can be used.
       > installed package ghc-9.0.1 is broken due to missing package exceptions-0.10.4
       >

[TeofilC]

The error you get in the 9.0.1 case looks like the error from this issue #1177

I tried a version of the patch recommended there:

diff --git a/overlay.nix b/overlay.nix
index aea8c98..213eb71 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -8,6 +8,22 @@ in
 {
   example = project' {
     src = ./.;
-    compiler-nix-name = "ghc8105";
-  };
+    compiler-nix-name = "ghc901";
+    modules = [{
+      nonReinstallablePkgs = [
+      "rts" "ghc-heap" "ghc-prim" "integer-gmp" "integer-simple" "base"
+      "deepseq" "array" "ghc-boot-th" "pretty" "template-haskell"
+      # ghcjs custom packages
+      "ghcjs-prim" "ghcjs-th"
+      "ghc-bignum" "exceptions" "stm"
+      "ghc-boot"
+      "ghc" "Cabal" "Win32" "array" "binary" "bytestring" "containers"
+      "directory" "filepath" "ghc-boot" "ghc-compact" "ghc-prim"
+      # "ghci" "haskeline"
+      "hpc"
+      "mtl" "parsec" "process" "text" "time" "transformers"
+      "unix" "xhtml" "terminfo"
+    ];
+  }];
+ };
 }

and that seems to compile it fine. I'm not sure if this helps you much, but at least it narrows it down to 8.10

[gilligan]

I just ran into this myself.

The problem stems from #825 : inspection-testing needs Tickish but CoreSyn doesn't export this constructor anymore with the patch applied.

I tried to patch inspection-testing but it isn't obvious to me what I should replace Tickish Id with and this leads me down a rabbit hole pretty quickly where the Breakpoint constructor doesn't match anymore either when I use CoreTickish instead.

[gilligan]

PS: I think this is a good reason to strongly consider #1301 - This patch introduces changes which aren't required for haskell.nix to work but are causing breakage. Thus it would be great if patches like this weren't enabled by default.

[michaelpj]

Hmm, actually I also encountered this, and was mystified. Yeah, messing with the types exposed by the ghc package is quite risky...

[michaelpj]

It just looks like overlays/patches/ghc/ghc-8.10.3-ubxt.patch and overlays/patches/ghc/ghc-8.10.5-ubxt.patch contain changes from another commit 🤔 Maybe we can just delete that?

[gilligan]

FTR i got everything to build using a fork that doesn’t apply the ubxt patches (as expected).

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jkachmar]

this is still an issue.