## Summary Fails with GHCs 9.6.2 and 9.4.5. Works with 9.2.8 though. ``` Resolving dependencies... Build profile: -w ghc-9.6.2 -O1 In order, the following will be built (use -v for more details): - haskhol-core-1.3.0 (lib) (configuration changed) Warning: HaskHOL-Core.cabal:12:22: Packages with 'cabal-version: 1.12' or later should specify a specific version of the Cabal spec of the form 'cabal-version: x.y'. Use 'cabal-version: 1.22'. Configuring library for haskhol-core-1.3.0.. Preprocessing library for haskhol-core-1.3.0.. Building library for haskhol-core-1.3.0.. [ 4 of 24] Compiling HaskHOL.Core.Kernel.Types <no location info>: error: panic! (the 'impossible' happened) GHC version 9.6.2: lookupIdSubst x_i8PE InScope {wild_00 tyorda_a7l5 alphavars_a7l6 tyordas_a7l7 $dMonad_a7Yf $dMonadCatch_a7YB $dMonadThrow_a7YT $cvalidSubst_a8fp $cvalidSubst_a8fE $cvalidSubst_a8fT $krep_a8ib $krep_a8ic $krep_a8id $krep_a8ie $krep_a8if $krep_a8ig $krep_a8ih $krep_a8ii $krep_a8ij $krep_a8ik $krep_a8il $krep_a8im $krep_a8in $krep_a8io a_i8Ho ds_i8Hp a_i8WW $dEq_i8WX l1_i8WY tyAlphaOrder tyAConv isVarType isType mkVarType destVarType destType tyVars catTyVars typeSubst typeSubstFull typeTypeSubst tyBool tyBottom tyA tyB destFunTy typeOf isTypeOpVar newPrimitiveTypeOp mkTypeOpVar destTypeOp tyOpBool tyOpBottom tyOpFun tyApp typeOpVars catTypeOpVars typeOpSubst typeOpInst isUType isSmall mkUType mkUTypes uTypeFromTypeOpVar mkSmall destUType destUTypes containsUType variantTyVar variantTyVars initTypeConstants typeMatch $tcTypeSubst $tc'C:TypeSubst $fTypeSubstTypeOpHOLType $fTypeSubstTypeOpTypeOp $fTypeSubstHOLTypeHOLType $mTyOpFun $mTyOpBool $mTyB $mTyA $mTyFun $m:-> $mTyBool $trModule $trModule_s8HR $trModule_s8HS $trModule_s8HT $trModule_s8HU $krep_s8HV $krep_s8HW $krep_s8HX $krep_s8HY $krep_s8HZ $tcTypeSubst_s8I0 $tcTypeSubst_s8I1 $krep_s8I2 $krep_s8I3 $tc'C:TypeSubst_s8I4 $tc'C:TypeSubst_s8I5 tyOpFun_s8IS tyOpFun_s8IT tyOpBottom_s8Ja tyOpBottom_s8Jb tyOpBool_s8Jc tyOpBool_s8Jd tyB_s8LQ tyA_s8LR catTypeOpVars_s8Xb} Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/GHC/Utils/Panic.hs:189:37 in ghc:GHC.Utils.Panic pprPanic, called at compiler/GHC/Core/Subst.hs:197:17 in ghc:GHC.Core.Subst CallStack (from HasCallStack): panic, called at compiler/GHC/Utils/Error.hs:454:29 in ghc:GHC.Utils.Error Please report this as a GHC bug: https://www.haskell.org/ghc/reportabug Error: cabal: Failed to build haskhol-core-1.3.0. ``` ## Steps to reproduce Download from github as Hackage version is likely outdated. - `git clone https://github.com/ecaustin/haskhol-core` - `cd haskhol-core` - `cabal build` ## Expected behavior Package builds without internal errors. May fail to build due to real errors though, haven't checked fully. ## Environment * GHC version used: 9.6.2, 9.4.5 * Operating System: Linux * System Architecture: amd64