Disable GHCs aggressive selection of ld.gold

.github/workflows/cross.yaml

@@ -21,8 +21,8 @@ jobs:
     name: Build linux binary
     runs-on: [self-hosted, Linux, X64, maerwald]
     env:
-      CABAL_VER: 3.10.1.0
-      JSON_VERSION: "0.0.7"
+      CABAL_VER: 3.10.3.0
+      JSON_VERSION: "0.0.8"
       AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
       AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
       S3_HOST: ${{ secrets.S3_HOST }}
@@ -31,7 +31,7 @@ jobs:
       ARCH: 64
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           submodules: 'true'
 
@@ -50,7 +50,7 @@ jobs:
 
       - if: always()
         name: Upload artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: artifacts
           path: |
@@ -61,13 +61,13 @@ jobs:
     needs: "build"
     runs-on: [self-hosted, Linux, X64]
     container:
-      image: registry.gitlab.haskell.org/ghc/ci-images/x86_64-linux-deb10:8d0224e6b2a08157649651e69302380b2bd24e11
+      image: registry.gitlab.haskell.org/ghc/ci-images/x86_64-linux-deb12:a9297a370025101b479cfd4977f8f910814e03ab
       options: --user root
       env:
-        CABAL_VER: 3.6.2.0
+        CABAL_VER: 3.10.3.0
         BUILD_CONF_ARGS: "--enable-unregisterised"
         HADRIAN_FLAVOUR: ""
-        JSON_VERSION: "0.0.7"
+        JSON_VERSION: "0.0.8"
         GHC_VER: 8.10.6
         GHC_TARGET_VERSION: "8.10.7"
         ARCH: 64
@@ -77,37 +77,44 @@ jobs:
         WRAPPER: "run"
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           submodules: 'true'
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: artifacts
           path: ./out
 
       - name: Run test (64 bit linux)
         run: |
           sudo apt-get update -y
-          sudo apt-get install -y libnuma-dev zlib1g-dev libgmp-dev libgmp10 libssl-dev liblzma-dev libbz2-dev git wget lsb-release software-properties-common gnupg2 apt-transport-https gcc autoconf automake build-essential curl gzip
-          sudo apt-get install -y gcc-arm-linux-gnueabihf
+          sudo apt-get install -y libnuma-dev zlib1g-dev libgmp-dev libgmp10 libssl-dev liblzma-dev libbz2-dev git wget lsb-release software-properties-common gnupg2 apt-transport-https gcc autoconf automake build-essential curl gzip libstdc++-11-dev
+          sudo apt-get install -y gcc-arm-linux-gnueabihf g++-arm-linux-gnueabihf
           sudo dpkg --add-architecture armhf
           sudo apt-get update -y
-          sudo apt-get install -y libncurses-dev:armhf
+          sudo apt-get install -y libncurses-dev:armhf libstdc++-11-dev:armhf
+          # ld.bfd is broken on armv7: https://sourceware.org/bugzilla/show_bug.cgi?id=16177
+          update-alternatives --install "/usr/bin/x86_64-linux-gnu-ld" "ld" "/usr/bin/x86_64-linux-gnu-ld.gold" 20
+          update-alternatives --install "/usr/bin/x86_64-linux-gnu-ld" "ld" "/usr/bin/x86_64-linux-gnu-ld.bfd" 10
+          update-alternatives --set "ld" "/usr/bin/x86_64-linux-gnu-ld.gold"
+          update-alternatives --install "/usr/bin/arm-linux-gnueabihf-ld" "ld-arm" "/usr/bin/arm-linux-gnueabihf-ld.gold" 20
+          update-alternatives --install "/usr/bin/arm-linux-gnueabihf-ld" "ld-arm" "/usr/bin/arm-linux-gnueabihf-ld.bfd" 10
+          update-alternatives --set "ld-arm" "/usr/bin/arm-linux-gnueabihf-ld.gold"
           sh .github/scripts/cross.sh
 
   test-cross-js:
     name: Test GHC JS cross
     needs: "build"
     runs-on: [self-hosted, Linux, X64]
     container:
-      image: registry.gitlab.haskell.org/ghc/ci-images/x86_64-linux-deb10:8d0224e6b2a08157649651e69302380b2bd24e11
+      image: registry.gitlab.haskell.org/ghc/ci-images/x86_64-linux-deb12:a9297a370025101b479cfd4977f8f910814e03ab
       options: --user root
       env:
-        CABAL_VER: 3.6.2.0
+        CABAL_VER: 3.10.3.0
         BUILD_CONF_ARGS: ""
         HADRIAN_FLAVOUR: "default+native_bignum"
-        JSON_VERSION: "0.0.7"
+        JSON_VERSION: "0.0.8"
         GHC_VER: 9.6.2
         GHC_TARGET_VERSION: "9.6.2"
         ARCH: 64
@@ -117,11 +124,11 @@ jobs:
         WRAPPER: "emconfigure"
     steps:
       - name: Checkout code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           submodules: 'true'
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: artifacts
           path: ./out

.github/workflows/release.yaml

@@ -126,6 +126,7 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ env.AWS_SECRET_ACCESS_KEY }}
           AWS_ACCESS_KEY_ID: ${{ env.AWS_ACCESS_KEY_ID }}
           S3_HOST: ${{ env.S3_HOST }}
+          LD: ld.gold
 
       - if: matrix.ARCH == 'ARM64'
         uses: docker://hasufell/arm64v8-debian-haskell:10
@@ -397,6 +398,7 @@ jobs:
           ARCH: ${{ matrix.ARCH }}
           GHC_VER: ${{ matrix.GHC_VER }}
           DISTRO: Ubuntu
+          LD: ld.gold
 
       - if: matrix.ARCH == 'ARM64'
         uses: docker://hasufell/arm64v8-debian-haskell:10

app/ghcup/Main.hs

@@ -90,6 +90,7 @@ toSettings options = do
          gpgSetting  = fromMaybe (fromMaybe (Types.gpgSetting defaultSettings) uGPGSetting) optGpg
          platformOverride = optPlatform <|> (uPlatformOverride <|> Types.platformOverride defaultSettings)
          mirrors  = fromMaybe (Types.mirrors defaultSettings) uMirrors
+         defGHCConfOptions  = fromMaybe (Types.defGHCConfOptions defaultSettings) uDefGHCConfOptions
      in (Settings {..}, keyBindings)
 #if defined(INTERNAL_DOWNLOADER)
    defaultDownloader = Internal

data/config.yaml

@@ -128,3 +128,12 @@ mirrors:
     authority:
       host: "mirror.sjtu.edu.cn"
 
+# Arguments to pass to the configure script of the prebuilt bindist.
+#
+# Do not pass '--prefix' here.
+#
+# GHCup by default passes '--disable-ld-override', so if you want to enable
+# the vanilla way, which aggressively favors 'ld.gold' linker, add the following:
+def-ghc-conf-options:
+  - "--enable-ld-override"
+

docs/guide.md

@@ -360,6 +360,28 @@ mirrors:
 
 The configuration depends on the host of the mirror and they have to provide the correct configuration.
 
+## Linkers
+
+The GHC bindist configure script by default doesn't honour the system `ld` that is set, but instead
+probes for `ld.lld`, `ld.gold` and only then `ld` in order, see
+[find_ld.m4](https://gitlab.haskell.org/ghc/ghc/-/blob/master/m4/find_ld.m4?ref_type=heads).
+
+This is controlled by the configure switch `--enable-ld-override`/`--disable-ld-override`, which is enabled by default in GHC.
+GHCup however [has decided](https://github.com/haskell/ghcup-hs/issues/1032) **to disable this switch by default**,
+for reasons of stability and simplicity.
+
+That means, when `--disable-ld-override` is passed, the linker is picked simply by:
+
+* checking if `LD` env var is set, then use whatever is specified
+* otherwise use `ld` binary in PATH (system/distro default)
+
+You can restore the GHC vanilla default by adding this to your `~/.ghcup/config.yaml`:
+
+```yaml
+def-ghc-conf-options:
+  - "--enable-ld-override"
+```
+
 # More on installation
 
 ## Customisation of the installation scripts

lib-opt/GHCup/OptParse/Config.hs

@@ -133,7 +133,8 @@ updateSettings usl usr =
        gpgSetting' = uGPGSetting usl <|> uGPGSetting usr
        platformOverride' = uPlatformOverride usl <|> uPlatformOverride usr
        mirrors' = uMirrors usl <|> uMirrors usr
-   in UserSettings cache' metaCache' metaMode' noVerify' verbose' keepDirs' downloader' (updateKeyBindings (uKeyBindings usl) (uKeyBindings usr)) urlSource' noNetwork' gpgSetting' platformOverride' mirrors'
+       defGHCconfOptions' = uDefGHCConfOptions usl <|> uDefGHCConfOptions usr
+   in UserSettings cache' metaCache' metaMode' noVerify' verbose' keepDirs' downloader' (updateKeyBindings (uKeyBindings usl) (uKeyBindings usr)) urlSource' noNetwork' gpgSetting' platformOverride' mirrors' defGHCconfOptions'
  where
   updateKeyBindings :: Maybe UserKeyBindings -> Maybe UserKeyBindings -> Maybe UserKeyBindings
   updateKeyBindings Nothing Nothing = Nothing

lib/GHCup/GHC.hs

@@ -439,46 +439,30 @@ installUnpackedGHC path inst tver forceInstall addConfArgs
       liftE $ mergeGHCFileTree path inst tver forceInstall
   | otherwise = do
       PlatformRequest {..} <- lift getPlatformReq
+      Settings {..} <- lift getSettings
 
-      let ldOverride
-           | _tvVersion tver >= [vver|8.2.2|]
-           , _rPlatform `elem` [Linux Alpine, Darwin]
-           = ["--disable-ld-override"]
-           | otherwise
-           = []
+      addConfArgs' <- sanitizefGHCconfOptions (T.unpack <$> addConfArgs)
+      defGHCConfOptions' <- sanitizefGHCconfOptions defGHCConfOptions
 
       lift $ logInfo "Installing GHC (this may take a while)"
-      env <- case _rPlatform of
-               -- https://github.com/haskell/ghcup-hs/issues/967
-               Linux Alpine
-                 -- lets not touch LD for cross targets
-                 | Nothing <- _tvTarget tver -> do
-                     cEnv <- liftIO getEnvironment
-                     spaths <- liftIO getSearchPath
-                     has_ld_bfd <- isJust <$> liftIO (searchPath spaths "ld.bfd")
-                     let ldSet = isJust $ lookup "LD" cEnv
-                     -- only set LD if ld.bfd exists in PATH and LD is not set
-                     -- already
-                     if has_ld_bfd && not ldSet
-                     then do
-                       lift $ logInfo "Detected alpine linux... setting LD=ld.bfd"
-                       pure $ Just (("LD", "ld.bfd") : cEnv)
-                     else pure Nothing
-               _ -> pure Nothing
       lEM $ execLogged "sh"
                        ("./configure" : ("--prefix=" <> fromInstallDir inst)
-                        : (maybe mempty (\x -> ["--target=" <> T.unpack x]) (_tvTarget tver) <> ldOverride <> (T.unpack <$> addConfArgs))
+                        : (maybe mempty (\x -> ["--target=" <> T.unpack x]) (_tvTarget tver)
+                          <> ldOverride (_tvVersion tver)
+                          <> defGHCConfOptions'
+                          <> addConfArgs')
                        )
                        (Just $ fromGHCupPath path)
                        "ghc-configure"
-                       env
+                       Nothing
       tmpInstallDest <- lift withGHCupTmpDir
       lEM $ make ["DESTDIR=" <> fromGHCupPath tmpInstallDest, "install"] (Just $ fromGHCupPath path)
       liftE $ catchWarn $ lEM @_ @'[ProcessError] $ darwinNotarization _rPlatform (fromGHCupPath tmpInstallDest)
       liftE $ mergeGHCFileTree (tmpInstallDest `appendGHCupPath` dropDrive (fromInstallDir inst)) inst tver forceInstall
       pure ()
 
 
+
 mergeGHCFileTree :: ( MonadReader env m
                     , HasPlatformReq env
                     , HasDirs env
@@ -1313,6 +1297,8 @@ compileGHC targetGhc crossTarget vps bstrap jobs mbuildConfig patches aargs buil
                 (_tvTarget tver)
       ++ ["--prefix=" <> ghcdir]
       ++ (if isWindows then ["--enable-tarballs-autodownload"] else [])
+      -- https://github.com/haskell/ghcup-hs/issues/1032
+      ++ ldOverride (_tvVersion tver)
       ++ fmap T.unpack aargs
       )
       (Just workdir)
@@ -1387,3 +1373,16 @@ postGHCInstall ver@GHCTargetVersion {..} = do
   forM_ v' $ \(mj, mi) -> lift (getGHCForPVP (PVP (fromIntegral mj :| [fromIntegral mi])) _tvTarget)
     >>= mapM_ (\v -> liftE $ setGHC v SetGHC_XY Nothing)
 
+
+ldOverride ::  Version -> [String]
+ldOverride ver
+  | ver >= [vver|8.2.2|]
+  = ["--disable-ld-override"]
+  | otherwise
+  = []
+
+sanitizefGHCconfOptions :: MonadFail m => [String] -> m [String]
+sanitizefGHCconfOptions args
+  | "--prefix" `elem` fmap (takeWhile (/= '=')) args = fail "Don't explicitly set --prefix ...aborting"
+  | otherwise = pure args
+

lib/GHCup/Types.hs

@@ -379,24 +379,25 @@ data MetaMode = Strict
 instance NFData MetaMode
 
 data UserSettings = UserSettings
-  { uCache       :: Maybe Bool
-  , uMetaCache   :: Maybe Integer
-  , uMetaMode    :: Maybe MetaMode
-  , uNoVerify    :: Maybe Bool
-  , uVerbose     :: Maybe Bool
-  , uKeepDirs    :: Maybe KeepDirs
-  , uDownloader  :: Maybe Downloader
-  , uKeyBindings :: Maybe UserKeyBindings
-  , uUrlSource   :: Maybe URLSource
-  , uNoNetwork   :: Maybe Bool
-  , uGPGSetting  :: Maybe GPGSetting
-  , uPlatformOverride :: Maybe PlatformRequest
-  , uMirrors     :: Maybe DownloadMirrors
+  { uCache             :: Maybe Bool
+  , uMetaCache         :: Maybe Integer
+  , uMetaMode          :: Maybe MetaMode
+  , uNoVerify          :: Maybe Bool
+  , uVerbose           :: Maybe Bool
+  , uKeepDirs          :: Maybe KeepDirs
+  , uDownloader        :: Maybe Downloader
+  , uKeyBindings       :: Maybe UserKeyBindings
+  , uUrlSource         :: Maybe URLSource
+  , uNoNetwork         :: Maybe Bool
+  , uGPGSetting        :: Maybe GPGSetting
+  , uPlatformOverride  :: Maybe PlatformRequest
+  , uMirrors           :: Maybe DownloadMirrors
+  , uDefGHCConfOptions :: Maybe [String]
   }
   deriving (Show, GHC.Generic, Eq)
 
 defaultUserSettings :: UserSettings
-defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
+defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
 
 fromSettings :: Settings -> Maybe KeyBindings -> UserSettings
 fromSettings Settings{..} Nothing =
@@ -414,6 +415,7 @@ fromSettings Settings{..} Nothing =
     , uGPGSetting = Just gpgSetting
     , uPlatformOverride = platformOverride
     , uMirrors = Just mirrors
+    , uDefGHCConfOptions = Just defGHCConfOptions
   }
 fromSettings Settings{..} (Just KeyBindings{..}) =
   let ukb = UserKeyBindings
@@ -440,6 +442,7 @@ fromSettings Settings{..} (Just KeyBindings{..}) =
     , uGPGSetting = Just gpgSetting
     , uPlatformOverride = platformOverride
     , uMirrors = Just mirrors
+    , uDefGHCConfOptions = Just defGHCConfOptions
   }
 
 data UserKeyBindings = UserKeyBindings
@@ -512,27 +515,28 @@ instance NFData LeanAppState
 
 
 data Settings = Settings
-  { cache            :: Bool
-  , metaCache        :: Integer
-  , metaMode         :: MetaMode
-  , noVerify         :: Bool
-  , keepDirs         :: KeepDirs
-  , downloader       :: Downloader
-  , verbose          :: Bool
-  , urlSource        :: URLSource
-  , noNetwork        :: Bool
-  , gpgSetting       :: GPGSetting
-  , noColor          :: Bool -- this also exists in LoggerConfig
-  , platformOverride :: Maybe PlatformRequest
-  , mirrors          :: DownloadMirrors
+  { cache             :: Bool
+  , metaCache         :: Integer
+  , metaMode          :: MetaMode
+  , noVerify          :: Bool
+  , keepDirs          :: KeepDirs
+  , downloader        :: Downloader
+  , verbose           :: Bool
+  , urlSource         :: URLSource
+  , noNetwork         :: Bool
+  , gpgSetting        :: GPGSetting
+  , noColor           :: Bool -- this also exists in LoggerConfig
+  , platformOverride  :: Maybe PlatformRequest
+  , mirrors           :: DownloadMirrors
+  , defGHCConfOptions :: [String]
   }
   deriving (Show, GHC.Generic)
 
 defaultMetaCache :: Integer
 defaultMetaCache = 300 -- 5 minutes
 
 defaultSettings :: Settings
-defaultSettings = Settings False defaultMetaCache Lax False Never Curl False GHCupURL False GPGNone False Nothing (DM mempty)
+defaultSettings = Settings False defaultMetaCache Lax False Never Curl False GHCupURL False GPGNone False Nothing (DM mempty) []
 
 instance NFData Settings