wip: introduce build and host toolchains

Author: andreabedini

cabal-install/src/Distribution/Client/Config.hs

@@ -573,6 +573,9 @@ instance Semigroup SavedConfig where
               combineMonoid savedConfigureExFlags configAllowOlder
           , configWriteGhcEnvironmentFilesPolicy =
               combine configWriteGhcEnvironmentFilesPolicy
+          , configHostHcFlavor = combine configHostHcFlavor
+          , configHostHcPath = combine configHostHcPath
+          , configHostHcPkg = combine configHostHcPkg
           }
         where
           combine = combine' savedConfigureExFlags

cabal-install/src/Distribution/Client/ProjectConfig/Legacy.hs

@@ -704,6 +704,13 @@ convertLegacyAllPackageFlags
 convertLegacyAllPackageFlags globalFlags configFlags configExFlags installFlags projectFlags projectConfigMultiRepl =
   ProjectConfigShared{..}
   where
+    projectConfigHostHcFlavor = NoFlag
+    projectConfigHostHcPath = NoFlag
+    projectConfigHostHcPkg = NoFlag
+    projectConfigPackageDBs = (fmap . fmap) (interpretPackageDB Nothing) projectConfigPackageDBs_
+    projectConfigHookHashes = mempty -- :: Map FilePath HookAccept
+    projectConfigDistDir = fmap getSymbolicPath projectConfigAbsoluteDistDir
+
     GlobalFlags
       { globalConfigFile = projectConfigConfigFile
       , globalRemoteRepos = projectConfigRemoteRepos
@@ -713,8 +720,6 @@ convertLegacyAllPackageFlags globalFlags configFlags configExFlags installFlags
       , globalStoreDir = projectConfigStoreDir
       } = globalFlags
 
-    projectConfigPackageDBs = (fmap . fmap) (interpretPackageDB Nothing) projectConfigPackageDBs_
-    projectConfigHookHashes = mempty -- :: Map FilePath HookAccept
     ConfigFlags
       { configCommonFlags = commonFlags
       , configHcFlavor = projectConfigHcFlavor
@@ -730,8 +735,6 @@ convertLegacyAllPackageFlags globalFlags configFlags configExFlags installFlags
       { setupDistPref = projectConfigAbsoluteDistDir
       } = commonFlags
 
-    projectConfigDistDir = fmap getSymbolicPath projectConfigAbsoluteDistDir
-
     ConfigExFlags
       { configCabalVersion = projectConfigCabalVersion
       , configExConstraints = projectConfigConstraints
@@ -1010,7 +1013,7 @@ convertToLegacySharedConfig
           }
 
       configExFlags =
-        ConfigExFlags
+        mempty
           { configCabalVersion = projectConfigCabalVersion
           , configAppend = mempty
           , configBackup = mempty

cabal-install/src/Distribution/Client/ProjectConfig/Types.hs

@@ -192,6 +192,9 @@ data ProjectConfigShared = ProjectConfigShared
   , projectConfigHcFlavor :: Flag CompilerFlavor
   , projectConfigHcPath :: Flag FilePath
   , projectConfigHcPkg :: Flag FilePath
+  , projectConfigHostHcFlavor :: Flag CompilerFlavor
+  , projectConfigHostHcPath :: Flag FilePath
+  , projectConfigHostHcPkg :: Flag FilePath
   , projectConfigHaddockIndex :: Flag PathTemplate
   , -- Only makes sense for manual mode, not --local mode
     -- too much control!

cabal-install/src/Distribution/Client/Setup.hs

@@ -162,7 +162,7 @@ import Distribution.ReadE
   )
 import Distribution.Simple.Command hiding (boolOpt, boolOpt')
 import qualified Distribution.Simple.Command as Command
-import Distribution.Simple.Compiler (Compiler, PackageDB, PackageDBStack)
+import Distribution.Simple.Compiler (Compiler, CompilerFlavor (..), PackageDB, PackageDBStack)
 import Distribution.Simple.Configure
   ( computeEffectiveProfiling
   , configCompilerAuxEx
@@ -920,6 +920,9 @@ data ConfigExFlags = ConfigExFlags
   , configAllowOlder :: Maybe AllowOlder
   , configWriteGhcEnvironmentFilesPolicy
       :: Flag WriteGhcEnvironmentFilesPolicy
+  , configHostHcFlavor :: Flag CompilerFlavor
+  , configHostHcPath :: Flag FilePath
+  , configHostHcPkg :: Flag FilePath
   }
   deriving (Eq, Show, Generic)
 
@@ -1047,6 +1050,31 @@ configureExOptions _showOrParseArgs src =
           writeGhcEnvironmentFilesPolicyParser
           writeGhcEnvironmentFilesPolicyPrinter
       )
+  , option
+      []
+      ["host-compiler"]
+      "host compiler"
+      configHostHcFlavor
+      (\v flags -> flags{configHostHcFlavor = v})
+      ( choiceOpt
+          [ (Flag GHC, ("g", ["ghc"]), "compile with GHC")
+          , (Flag GHCJS, ([], ["ghcjs"]), "compile with GHCJS")
+          ]
+      )
+  , option
+      "W"
+      ["with-host-compiler", "with-host-hc"]
+      "give the path to the compiler for the host toolchain"
+      configHostHcPath
+      (\v flags -> flags{configHostHcPath = v})
+      (reqArgFlag "PATH")
+  , option
+      ""
+      ["with-host-hc-pkg"]
+      "give the path to the package tool for the host toolchain"
+      configHostHcPkg
+      (\v flags -> flags{configHostHcPkg = v})
+      (reqArgFlag "PATH")
   ]
 
 writeGhcEnvironmentFilesPolicyParser :: ReadE (Flag WriteGhcEnvironmentFilesPolicy)