[GHC] #14759: ListSetOps WARNING causes tests to fail

Mon Feb 5 00:31:00 UTC 2018

#14759: ListSetOps WARNING causes tests to fail
-------------------------------------+-------------------------------------
        Reporter:  ezyang            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Description changed by ezyang:

Old description:

> Example log:
>
> ```
> +WARNING: file compiler/utils/ListSetOps.hs, line 58
> +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
> +   Distribution.Backpack.ModuleShape,
> +   Distribution.Backpack.PreModuleShape,
> +   Distribution.Backpack.ReadyComponent,
> +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
> +   Distribution.Compat.Semigroup, Distribution.Compiler,
> +   Distribution.License, Distribution.ModuleName,
> +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
> +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
> +   Distribution.SPDX.LicenseReference,
> +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
> +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
> +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
> +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
> +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
> +   Distribution.System, Distribution.Types.AbiDependency,
> +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
> +   Distribution.Types.BenchmarkInterface,
> +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
> +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
> +   Distribution.Types.ComponentLocalBuildInfo,
> +   Distribution.Types.ComponentName,
> +   Distribution.Types.ComponentRequestedSpec,
> +   Distribution.Types.CondTree, Distribution.Types.Condition,
> +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
> +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
> +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
> +   Distribution.Types.ForeignLibOption,
> +   Distribution.Types.ForeignLibType,
> +   Distribution.Types.GenericPackageDescription,
> +   Distribution.Types.IncludeRenaming,
> +   Distribution.Types.InstalledPackageInfo,
> +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
> +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
> +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
> +   Distribution.Types.ModuleRenaming,
> +   Distribution.Types.MungedPackageId,
> +   Distribution.Types.MungedPackageName,
> +   Distribution.Types.PackageDescription,
> +   Distribution.Types.PackageId, Distribution.Types.PackageName,
> +   Distribution.Types.PkgconfigDependency,
> +   Distribution.Types.PkgconfigName,
> +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
> +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
> +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
> +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
> +   Distribution.Types.Version, Distribution.Types.VersionRange,
> +   Distribution.Utils.ShortText, Distribution.Verbosity,
> +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
> +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
> +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
> +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
> +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
> +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
> +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
> +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
> +   Data.Text, Data.Text.Lazy]
> +  []
> +WARNING: file compiler/utils/ListSetOps.hs, line 58
> +  [Control.Applicative, Data.Functor.Const, Data.Functor.Identity,
> +   Data.Monoid, Data.Semigroup.Internal, GHC.Generics,
> +   GHC.IO.Exception]
> +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
> +   Distribution.Backpack.ModuleShape,
> +   Distribution.Backpack.PreModuleShape,
> +   Distribution.Backpack.ReadyComponent,
> +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
> +   Distribution.Compat.Semigroup, Distribution.Compiler,
> +   Distribution.License, Distribution.ModuleName,
> +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
> +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
> +   Distribution.SPDX.LicenseReference,
> +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
> +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
> +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
> +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
> +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
> +   Distribution.System, Distribution.Types.AbiDependency,
> +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
> +   Distribution.Types.BenchmarkInterface,
> +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
> +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
> +   Distribution.Types.ComponentLocalBuildInfo,
> +   Distribution.Types.ComponentName,
> +   Distribution.Types.ComponentRequestedSpec,
> +   Distribution.Types.CondTree, Distribution.Types.Condition,
> +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
> +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
> +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
> +   Distribution.Types.ForeignLibOption,
> +   Distribution.Types.ForeignLibType,
> +   Distribution.Types.GenericPackageDescription,
> +   Distribution.Types.IncludeRenaming,
> +   Distribution.Types.InstalledPackageInfo,
> +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
> +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
> +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
> +   Distribution.Types.ModuleRenaming,
> +   Distribution.Types.MungedPackageId,
> +   Distribution.Types.MungedPackageName,
> +   Distribution.Types.PackageDescription,
> +   Distribution.Types.PackageId, Distribution.Types.PackageName,
> +   Distribution.Types.PkgconfigDependency,
> +   Distribution.Types.PkgconfigName,
> +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
> +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
> +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
> +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
> +   Distribution.Types.Version, Distribution.Types.VersionRange,
> +   Distribution.Utils.ShortText, Distribution.Verbosity,
> +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
> +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
> +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
> +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
> +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
> +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
> +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
> +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
> +   Data.Text, Data.Text.Lazy]
> +WARNING: file compiler/utils/ListSetOps.hs, line 58
> +  []
> +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
> +   Distribution.Backpack.ModuleShape,
> +   Distribution.Backpack.PreModuleShape,
> +   Distribution.Backpack.ReadyComponent,
> +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
> +   Distribution.Compat.Semigroup, Distribution.Compiler,
> +   Distribution.License, Distribution.ModuleName,
> +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
> +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
> +   Distribution.SPDX.LicenseReference,
> +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
> +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
> +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
> +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
> +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
> +   Distribution.System, Distribution.Types.AbiDependency,
> +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
> +   Distribution.Types.BenchmarkInterface,
> +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
> +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
> +   Distribution.Types.ComponentLocalBuildInfo,
> +   Distribution.Types.ComponentName,
> +   Distribution.Types.ComponentRequestedSpec,
> +   Distribution.Types.CondTree, Distribution.Types.Condition,
> +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
> +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
> +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
> +   Distribution.Types.ForeignLibOption,
> +   Distribution.Types.ForeignLibType,
> +   Distribution.Types.GenericPackageDescription,
> +   Distribution.Types.IncludeRenaming,
> +   Distribution.Types.InstalledPackageInfo,
> +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
> +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
> +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
> +   Distribution.Types.ModuleRenaming,
> +   Distribution.Types.MungedPackageId,
> +   Distribution.Types.MungedPackageName,
> +   Distribution.Types.PackageDescription,
> +   Distribution.Types.PackageId, Distribution.Types.PackageName,
> +   Distribution.Types.PkgconfigDependency,
> +   Distribution.Types.PkgconfigName,
> +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
> +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
> +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
> +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
> +   Distribution.Types.Version, Distribution.Types.VersionRange,
> +   Distribution.Utils.ShortText, Distribution.Verbosity,
> +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
> +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
> +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
> +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
> +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
> +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
> +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
> +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
> +   Data.Text, Data.Text.Lazy]
> +WARNING: file compiler/utils/ListSetOps.hs, line 58
> +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
> +   Distribution.Backpack.ModuleShape,
> +   Distribution.Backpack.PreModuleShape,
> +   Distribution.Backpack.ReadyComponent,
> +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
> +   Distribution.Compat.Semigroup, Distribution.Compiler,
> +   Distribution.License, Distribution.ModuleName,
> +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
> +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
> +   Distribution.SPDX.LicenseReference,
> +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
> +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
> +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
> +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
> +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
> +   Distribution.System, Distribution.Types.AbiDependency,
> +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
> +   Distribution.Types.BenchmarkInterface,
> +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
> +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
> +   Distribution.Types.ComponentLocalBuildInfo,
> +   Distribution.Types.ComponentName,
> +   Distribution.Types.ComponentRequestedSpec,
> +   Distribution.Types.CondTree, Distribution.Types.Condition,
> +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
> +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
> +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
> +   Distribution.Types.ForeignLibOption,
> +   Distribution.Types.ForeignLibType,
> +   Distribution.Types.GenericPackageDescription,
> +   Distribution.Types.IncludeRenaming,
> +   Distribution.Types.InstalledPackageInfo,
> +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
> +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
> +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
> +   Distribution.Types.ModuleRenaming,
> +   Distribution.Types.MungedPackageId,
> +   Distribution.Types.MungedPackageName,
> +   Distribution.Types.PackageDescription,
> +   Distribution.Types.PackageId, Distribution.Types.PackageName,
> +   Distribution.Types.PkgconfigDependency,
> +   Distribution.Types.PkgconfigName,
> +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
> +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
> +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
> +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
> +   Distribution.Types.Version, Distribution.Types.VersionRange,
> +   Distribution.Utils.ShortText, Distribution.Verbosity,
> +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
> +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
> +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
> +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
> +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
> +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
> +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
> +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
> +   Data.Text, Data.Text.Lazy]
> +  []
> *** unexpected failure for cabal09(normal)
> ```
>
> This is probably orph calculation.

New description:

 Example log:

 {{{
 +WARNING: file compiler/utils/ListSetOps.hs, line 58
 +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
 +   Distribution.Backpack.ModuleShape,
 +   Distribution.Backpack.PreModuleShape,
 +   Distribution.Backpack.ReadyComponent,
 +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
 +   Distribution.Compat.Semigroup, Distribution.Compiler,
 +   Distribution.License, Distribution.ModuleName,
 +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
 +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
 +   Distribution.SPDX.LicenseReference,
 +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
 +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
 +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
 +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
 +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
 +   Distribution.System, Distribution.Types.AbiDependency,
 +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
 +   Distribution.Types.BenchmarkInterface,
 +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
 +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
 +   Distribution.Types.ComponentLocalBuildInfo,
 +   Distribution.Types.ComponentName,
 +   Distribution.Types.ComponentRequestedSpec,
 +   Distribution.Types.CondTree, Distribution.Types.Condition,
 +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
 +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
 +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
 +   Distribution.Types.ForeignLibOption,
 +   Distribution.Types.ForeignLibType,
 +   Distribution.Types.GenericPackageDescription,
 +   Distribution.Types.IncludeRenaming,
 +   Distribution.Types.InstalledPackageInfo,
 +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
 +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
 +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
 +   Distribution.Types.ModuleRenaming,
 +   Distribution.Types.MungedPackageId,
 +   Distribution.Types.MungedPackageName,
 +   Distribution.Types.PackageDescription,
 +   Distribution.Types.PackageId, Distribution.Types.PackageName,
 +   Distribution.Types.PkgconfigDependency,
 +   Distribution.Types.PkgconfigName,
 +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
 +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
 +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
 +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
 +   Distribution.Types.Version, Distribution.Types.VersionRange,
 +   Distribution.Utils.ShortText, Distribution.Verbosity,
 +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
 +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
 +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
 +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
 +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
 +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
 +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
 +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
 +   Data.Text, Data.Text.Lazy]
 +  []
 +WARNING: file compiler/utils/ListSetOps.hs, line 58
 +  [Control.Applicative, Data.Functor.Const, Data.Functor.Identity,
 +   Data.Monoid, Data.Semigroup.Internal, GHC.Generics,
 +   GHC.IO.Exception]
 +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
 +   Distribution.Backpack.ModuleShape,
 +   Distribution.Backpack.PreModuleShape,
 +   Distribution.Backpack.ReadyComponent,
 +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
 +   Distribution.Compat.Semigroup, Distribution.Compiler,
 +   Distribution.License, Distribution.ModuleName,
 +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
 +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
 +   Distribution.SPDX.LicenseReference,
 +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
 +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
 +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
 +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
 +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
 +   Distribution.System, Distribution.Types.AbiDependency,
 +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
 +   Distribution.Types.BenchmarkInterface,
 +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
 +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
 +   Distribution.Types.ComponentLocalBuildInfo,
 +   Distribution.Types.ComponentName,
 +   Distribution.Types.ComponentRequestedSpec,
 +   Distribution.Types.CondTree, Distribution.Types.Condition,
 +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
 +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
 +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
 +   Distribution.Types.ForeignLibOption,
 +   Distribution.Types.ForeignLibType,
 +   Distribution.Types.GenericPackageDescription,
 +   Distribution.Types.IncludeRenaming,
 +   Distribution.Types.InstalledPackageInfo,
 +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
 +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
 +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
 +   Distribution.Types.ModuleRenaming,
 +   Distribution.Types.MungedPackageId,
 +   Distribution.Types.MungedPackageName,
 +   Distribution.Types.PackageDescription,
 +   Distribution.Types.PackageId, Distribution.Types.PackageName,
 +   Distribution.Types.PkgconfigDependency,
 +   Distribution.Types.PkgconfigName,
 +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
 +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
 +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
 +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
 +   Distribution.Types.Version, Distribution.Types.VersionRange,
 +   Distribution.Utils.ShortText, Distribution.Verbosity,
 +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
 +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
 +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
 +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
 +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
 +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
 +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
 +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
 +   Data.Text, Data.Text.Lazy]
 +WARNING: file compiler/utils/ListSetOps.hs, line 58
 +  []
 +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
 +   Distribution.Backpack.ModuleShape,
 +   Distribution.Backpack.PreModuleShape,
 +   Distribution.Backpack.ReadyComponent,
 +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
 +   Distribution.Compat.Semigroup, Distribution.Compiler,
 +   Distribution.License, Distribution.ModuleName,
 +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
 +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
 +   Distribution.SPDX.LicenseReference,
 +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
 +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
 +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
 +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
 +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
 +   Distribution.System, Distribution.Types.AbiDependency,
 +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
 +   Distribution.Types.BenchmarkInterface,
 +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
 +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
 +   Distribution.Types.ComponentLocalBuildInfo,
 +   Distribution.Types.ComponentName,
 +   Distribution.Types.ComponentRequestedSpec,
 +   Distribution.Types.CondTree, Distribution.Types.Condition,
 +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
 +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
 +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
 +   Distribution.Types.ForeignLibOption,
 +   Distribution.Types.ForeignLibType,
 +   Distribution.Types.GenericPackageDescription,
 +   Distribution.Types.IncludeRenaming,
 +   Distribution.Types.InstalledPackageInfo,
 +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
 +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
 +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
 +   Distribution.Types.ModuleRenaming,
 +   Distribution.Types.MungedPackageId,
 +   Distribution.Types.MungedPackageName,
 +   Distribution.Types.PackageDescription,
 +   Distribution.Types.PackageId, Distribution.Types.PackageName,
 +   Distribution.Types.PkgconfigDependency,
 +   Distribution.Types.PkgconfigName,
 +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
 +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
 +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
 +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
 +   Distribution.Types.Version, Distribution.Types.VersionRange,
 +   Distribution.Utils.ShortText, Distribution.Verbosity,
 +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
 +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
 +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
 +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
 +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
 +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
 +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
 +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
 +   Data.Text, Data.Text.Lazy]
 +WARNING: file compiler/utils/ListSetOps.hs, line 58
 +  [Distribution.Backpack, Distribution.Backpack.FullUnitId,
 +   Distribution.Backpack.ModuleShape,
 +   Distribution.Backpack.PreModuleShape,
 +   Distribution.Backpack.ReadyComponent,
 +   Distribution.CabalSpecVersion, Distribution.Compat.Graph,
 +   Distribution.Compat.Semigroup, Distribution.Compiler,
 +   Distribution.License, Distribution.ModuleName,
 +   Distribution.SPDX.License, Distribution.SPDX.LicenseExceptionId,
 +   Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId,
 +   Distribution.SPDX.LicenseReference,
 +   Distribution.Simple.BuildTarget, Distribution.Simple.Compiler,
 +   Distribution.Simple.Doctest, Distribution.Simple.Haddock,
 +   Distribution.Simple.InstallDirs, Distribution.Simple.PackageIndex,
 +   Distribution.Simple.Program.Find, Distribution.Simple.Program.GHC,
 +   Distribution.Simple.Program.Types, Distribution.Simple.Setup,
 +   Distribution.System, Distribution.Types.AbiDependency,
 +   Distribution.Types.AbiHash, Distribution.Types.Benchmark,
 +   Distribution.Types.BenchmarkInterface,
 +   Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo,
 +   Distribution.Types.BuildType, Distribution.Types.ComponentId,
 +   Distribution.Types.ComponentLocalBuildInfo,
 +   Distribution.Types.ComponentName,
 +   Distribution.Types.ComponentRequestedSpec,
 +   Distribution.Types.CondTree, Distribution.Types.Condition,
 +   Distribution.Types.Dependency, Distribution.Types.ExeDependency,
 +   Distribution.Types.Executable, Distribution.Types.ExecutableScope,
 +   Distribution.Types.ExposedModule, Distribution.Types.ForeignLib,
 +   Distribution.Types.ForeignLibOption,
 +   Distribution.Types.ForeignLibType,
 +   Distribution.Types.GenericPackageDescription,
 +   Distribution.Types.IncludeRenaming,
 +   Distribution.Types.InstalledPackageInfo,
 +   Distribution.Types.LegacyExeDependency, Distribution.Types.Library,
 +   Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin,
 +   Distribution.Types.Module, Distribution.Types.ModuleReexport,
 +   Distribution.Types.ModuleRenaming,
 +   Distribution.Types.MungedPackageId,
 +   Distribution.Types.MungedPackageName,
 +   Distribution.Types.PackageDescription,
 +   Distribution.Types.PackageId, Distribution.Types.PackageName,
 +   Distribution.Types.PkgconfigDependency,
 +   Distribution.Types.PkgconfigName,
 +   Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo,
 +   Distribution.Types.TargetInfo, Distribution.Types.TestSuite,
 +   Distribution.Types.TestSuiteInterface, Distribution.Types.TestType,
 +   Distribution.Types.UnitId, Distribution.Types.UnqualComponentName,
 +   Distribution.Types.Version, Distribution.Types.VersionRange,
 +   Distribution.Utils.ShortText, Distribution.Verbosity,
 +   Language.Haskell.Extension, Control.Applicative, Data.Complex,
 +   Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity,
 +   Data.Functor.Product, Data.Functor.Sum, Data.Monoid,
 +   Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void,
 +   GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph,
 +   Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal,
 +   Data.Sequence.Internal, Data.Set.Internal, Data.Tree,
 +   Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ,
 +   Data.Text, Data.Text.Lazy]
 +  []
 *** unexpected failure for cabal09(normal)
 }}}

 This is probably orph calculation.

--

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14759#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler