Problem with GHC saying `<command line>: unknown package: integer-gmp` when Cabal built with an integer-gmp GHC is used in a build of a GHC with integer-simple

Cabal-2.4.1.0-9MZFDeNrcJI10bcroa6pq8.conf

name: Cabal
version: 2.4.1.0
id: Cabal-2.4.1.0-9MZFDeNrcJI10bcroa6pq8
key: Cabal-2.4.1.0-9MZFDeNrcJI10bcroa6pq8
license: BSD-3-Clause
copyright: 2003-2018, Cabal Development Team (see AUTHORS file)
maintainer: cabal-devel@haskell.org
author: Cabal Development Team <cabal-devel@haskell.org>
homepage: http://www.haskell.org/cabal/
synopsis: A framework for packaging Haskell software
description:
    The Haskell Common Architecture for Building Applications and
    Libraries: a framework defining a common interface for authors to more
    easily build their Haskell applications in a portable way.
    .
    The Haskell Cabal is part of a larger infrastructure for distributing,
    organizing, and cataloging Haskell libraries and tools.
category: Distribution
abi: 1836a37eafc57c547e7ec68828aed87e
exposed: True
exposed-modules:
    Distribution.Backpack Distribution.Backpack.ComponentsGraph
    Distribution.Backpack.Configure
    Distribution.Backpack.ConfiguredComponent
    Distribution.Backpack.DescribeUnitId
    Distribution.Backpack.FullUnitId
    Distribution.Backpack.LinkedComponent
    Distribution.Backpack.ModSubst Distribution.Backpack.ModuleShape
    Distribution.Backpack.PreModuleShape Distribution.CabalSpecVersion
    Distribution.Compat.Binary Distribution.Compat.CharParsing
    Distribution.Compat.CreatePipe Distribution.Compat.DList
    Distribution.Compat.Directory Distribution.Compat.Environment
    Distribution.Compat.Exception Distribution.Compat.Graph
    Distribution.Compat.Internal.TempFile Distribution.Compat.Lens
    Distribution.Compat.Newtype Distribution.Compat.Parsing
    Distribution.Compat.Prelude.Internal Distribution.Compat.ReadP
    Distribution.Compat.Semigroup Distribution.Compat.Stack
    Distribution.Compat.Time Distribution.Compiler
    Distribution.FieldGrammar Distribution.FieldGrammar.Class
    Distribution.FieldGrammar.FieldDescrs
    Distribution.FieldGrammar.Parsec Distribution.FieldGrammar.Pretty
    Distribution.InstalledPackageInfo Distribution.License
    Distribution.Make Distribution.ModuleName Distribution.Package
    Distribution.PackageDescription
    Distribution.PackageDescription.Check
    Distribution.PackageDescription.Configuration
    Distribution.PackageDescription.FieldGrammar
    Distribution.PackageDescription.Parsec
    Distribution.PackageDescription.PrettyPrint
    Distribution.PackageDescription.Quirks
    Distribution.PackageDescription.Utils Distribution.ParseUtils
    Distribution.Parsec.Class Distribution.Parsec.Common
    Distribution.Parsec.ConfVar Distribution.Parsec.Field
    Distribution.Parsec.FieldLineStream Distribution.Parsec.Lexer
    Distribution.Parsec.LexerMonad Distribution.Parsec.Newtypes
    Distribution.Parsec.ParseResult Distribution.Parsec.Parser
    Distribution.Pretty Distribution.PrettyUtils Distribution.ReadE
    Distribution.SPDX Distribution.SPDX.License
    Distribution.SPDX.LicenseExceptionId
    Distribution.SPDX.LicenseExpression Distribution.SPDX.LicenseId
    Distribution.SPDX.LicenseListVersion
    Distribution.SPDX.LicenseReference Distribution.Simple
    Distribution.Simple.Bench Distribution.Simple.Build
    Distribution.Simple.Build.Macros
    Distribution.Simple.Build.PathsModule
    Distribution.Simple.BuildPaths Distribution.Simple.BuildTarget
    Distribution.Simple.BuildToolDepends Distribution.Simple.CCompiler
    Distribution.Simple.Command Distribution.Simple.Compiler
    Distribution.Simple.Configure Distribution.Simple.Doctest
    Distribution.Simple.Flag Distribution.Simple.GHC
    Distribution.Simple.GHCJS Distribution.Simple.Glob
    Distribution.Simple.Haddock Distribution.Simple.HaskellSuite
    Distribution.Simple.Hpc Distribution.Simple.Install
    Distribution.Simple.InstallDirs Distribution.Simple.LocalBuildInfo
    Distribution.Simple.PackageIndex Distribution.Simple.PreProcess
    Distribution.Simple.PreProcess.Unlit Distribution.Simple.Program
    Distribution.Simple.Program.Ar Distribution.Simple.Program.Builtin
    Distribution.Simple.Program.Db Distribution.Simple.Program.Find
    Distribution.Simple.Program.GHC Distribution.Simple.Program.HcPkg
    Distribution.Simple.Program.Hpc
    Distribution.Simple.Program.Internal Distribution.Simple.Program.Ld
    Distribution.Simple.Program.ResponseFile
    Distribution.Simple.Program.Run Distribution.Simple.Program.Script
    Distribution.Simple.Program.Strip Distribution.Simple.Program.Types
    Distribution.Simple.Register Distribution.Simple.Setup
    Distribution.Simple.SrcDist Distribution.Simple.Test
    Distribution.Simple.Test.ExeV10 Distribution.Simple.Test.LibV09
    Distribution.Simple.Test.Log Distribution.Simple.UHC
    Distribution.Simple.UserHooks Distribution.Simple.Utils
    Distribution.System Distribution.TestSuite Distribution.Text
    Distribution.Types.AbiDependency Distribution.Types.AbiHash
    Distribution.Types.AnnotatedId Distribution.Types.Benchmark
    Distribution.Types.Benchmark.Lens
    Distribution.Types.BenchmarkInterface
    Distribution.Types.BenchmarkType Distribution.Types.BuildInfo
    Distribution.Types.BuildInfo.Lens Distribution.Types.BuildType
    Distribution.Types.Component Distribution.Types.ComponentId
    Distribution.Types.ComponentInclude
    Distribution.Types.ComponentLocalBuildInfo
    Distribution.Types.ComponentName
    Distribution.Types.ComponentRequestedSpec
    Distribution.Types.CondTree Distribution.Types.Condition
    Distribution.Types.Dependency Distribution.Types.DependencyMap
    Distribution.Types.ExeDependency Distribution.Types.Executable
    Distribution.Types.Executable.Lens
    Distribution.Types.ExecutableScope Distribution.Types.ExposedModule
    Distribution.Types.ForeignLib Distribution.Types.ForeignLib.Lens
    Distribution.Types.ForeignLibOption
    Distribution.Types.ForeignLibType
    Distribution.Types.GenericPackageDescription
    Distribution.Types.GenericPackageDescription.Lens
    Distribution.Types.HookedBuildInfo
    Distribution.Types.IncludeRenaming
    Distribution.Types.InstalledPackageInfo
    Distribution.Types.InstalledPackageInfo.FieldGrammar
    Distribution.Types.InstalledPackageInfo.Lens
    Distribution.Types.LegacyExeDependency Distribution.Types.Lens
    Distribution.Types.Library Distribution.Types.Library.Lens
    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.PackageDescription.Lens
    Distribution.Types.PackageId Distribution.Types.PackageId.Lens
    Distribution.Types.PackageName
    Distribution.Types.PkgconfigDependency
    Distribution.Types.PkgconfigName Distribution.Types.SetupBuildInfo
    Distribution.Types.SetupBuildInfo.Lens
    Distribution.Types.SourceRepo Distribution.Types.SourceRepo.Lens
    Distribution.Types.TargetInfo Distribution.Types.TestSuite
    Distribution.Types.TestSuite.Lens
    Distribution.Types.TestSuiteInterface Distribution.Types.TestType
    Distribution.Types.UnitId Distribution.Types.UnqualComponentName
    Distribution.Types.Version Distribution.Types.VersionInterval
    Distribution.Types.VersionRange Distribution.Utils.Generic
    Distribution.Utils.IOData Distribution.Utils.LogProgress
    Distribution.Utils.MapAccum Distribution.Utils.NubList
    Distribution.Utils.Progress Distribution.Utils.ShortText
    Distribution.Verbosity Distribution.Version
    Language.Haskell.Extension
hidden-modules: Distribution.Backpack.PreExistingComponent
                Distribution.Backpack.ReadyComponent Distribution.Backpack.MixLink
                Distribution.Backpack.ModuleScope Distribution.Backpack.UnifyM
                Distribution.Backpack.Id Distribution.Utils.UnionFind
                Distribution.Utils.Base62 Distribution.Compat.CopyFile
                Distribution.Compat.GetShortPathName Distribution.Compat.MonadFail
                Distribution.Compat.Prelude Distribution.Compat.SnocList
                Distribution.GetOpt Distribution.Lex Distribution.Utils.String
                Distribution.Simple.GHC.EnvironmentParser
                Distribution.Simple.GHC.Internal Distribution.Simple.GHC.ImplInfo
                Paths_Cabal
import-dirs: /nix/store/8rrbqv4nbd622h6a8c0xyxfwb5cjvh63-Cabal-2.4.1.0/lib/ghc-8.6.4/x86_64-linux-ghc-8.6.4/Cabal-2.4.1.0-9MZFDeNrcJI10bcroa6pq8
library-dirs: /nix/store/8rrbqv4nbd622h6a8c0xyxfwb5cjvh63-Cabal-2.4.1.0/lib/ghc-8.6.4/x86_64-linux-ghc-8.6.4/Cabal-2.4.1.0-9MZFDeNrcJI10bcroa6pq8
              /nix/store/dh0cgwacpb93lbm3ib8sfynb8b6w55f1-ncurses-6.1-20190112/lib
              /nix/store/01403y06ix2g63c875wl5h3v4imwjqgx-libffi-3.2.1/lib
              /nix/store/qkvzv6n1igh2rd2rzmslpzdv720ddqp9-gmp-6.1.2/lib
dynamic-library-dirs: /nix/store/8rrbqv4nbd622h6a8c0xyxfwb5cjvh63-Cabal-2.4.1.0/lib/ghc-8.6.4/x86_64-linux-ghc-8.6.4
                      /nix/store/dh0cgwacpb93lbm3ib8sfynb8b6w55f1-ncurses-6.1-20190112/lib
                      /nix/store/01403y06ix2g63c875wl5h3v4imwjqgx-libffi-3.2.1/lib
                      /nix/store/qkvzv6n1igh2rd2rzmslpzdv720ddqp9-gmp-6.1.2/lib
data-dir: /nix/store/8rrbqv4nbd622h6a8c0xyxfwb5cjvh63-Cabal-2.4.1.0/share/x86_64-linux-ghc-8.6.4/Cabal-2.4.1.0
hs-libraries: HSCabal-2.4.1.0-9MZFDeNrcJI10bcroa6pq8
include-dirs: /nix/store/5s4ra1jvlh545f1l22cpg1h2xzqy92xh-musl-iconv-1.1.22/include
depends:
    array-0.5.3.0 base-4.12.0.0 binary-0.8.6.0 bytestring-0.10.8.2
    containers-0.6.0.1 deepseq-1.4.4.0 directory-1.3.3.0
    filepath-1.4.2.1 mtl-2.2.2 parsec-3.1.13.0 pretty-1.1.3.6
    process-1.6.5.0 text-1.2.3.1 time-1.8.0.2 transformers-0.5.6.2
    unix-2.7.2.2
haddock-interfaces: /nix/store/8823rp4ff47xh9lpbj47czrnwrf1pava-Cabal-2.4.1.0-doc/share/doc/Cabal-2.4.1.0/html/Cabal.haddock
haddock-html: /nix/store/8823rp4ff47xh9lpbj47czrnwrf1pava-Cabal-2.4.1.0-doc/share/doc/Cabal-2.4.1.0/html