Merge pull request #129289 from nh2/issue-129247-ghc-musl-fixes

Fix GHC not building with musl

6 files changed, 414 insertions, 86 deletions

diff --git a/pkgs/development/compilers/ghc/8.10.2-binary.nix b/pkgs/development/compilers/ghc/8.10.2-binary.nix
index ad1a47e5cc9..3ef4ebb9b98 100644
--- a/pkgs/development/compilers/ghc/8.10.2-binary.nix
+++ b/pkgs/development/compilers/ghc/8.10.2-binary.nix
@@ -1,6 +1,7 @@
 { lib, stdenv
 , fetchurl, perl, gcc
-, ncurses6, gmp, glibc, libiconv, numactl
+, ncurses5
+, ncurses6, gmp, libiconv, numactl
 , llvmPackages
 
   # minimal = true; will remove files that aren't strictly necessary for
@@ -14,68 +15,191 @@
 assert stdenv.targetPlatform == stdenv.hostPlatform;
 
 let
+  downloadsUrl = "https://downloads.haskell.org/ghc";
+
+  version = "8.10.2";
+
+  # Information about available bindists that we use in the build.
+  #
+  # # Bindist library checking
+  #
+  # The field `archSpecificLibraries` also provides a way for us get notified
+  # early when the upstream bindist changes its dependencies (e.g. because a
+  # newer Debian version is used that uses a new `ncurses` version).
+  #
+  # Usage:
+  #
+  # * You can find the `fileToCheckFor` of libraries by running `readelf -d`
+  #   on the compiler binary (`exePathForLibraryCheck`).
+  # * To skip library checking for an architecture,
+  #   set `exePathForLibraryCheck = null`.
+  # * To skip file checking for a specific arch specfic library,
+  #   set `fileToCheckFor = null`.
+  ghcBinDists = {
+    # Binary distributions for the default libc (e.g. glibc, or libSystem on Darwin)
+    # nixpkgs uses for the respective system.
+    defaultLibc = {
+      i686-linux = {
+        src = {
+          url = "${downloadsUrl}/${version}/ghc-${version}-i386-deb9-linux.tar.xz";
+          sha256 = "0bvwisl4w0z5z8z0da10m9sv0mhm9na2qm43qxr8zl23mn32mblx";
+        };
+        exePathForLibraryCheck = "ghc/stage2/build/tmp/ghc-stage2";
+        archSpecificLibraries = [
+          # The i686-linux bindist provided by GHC HQ is currently built on Debian 9,
+          # which link it against `libtinfo.so.5` (ncurses 5).
+          # Other bindists are linked `libtinfo.so.6` (ncurses 6).
+          { nixPackage = ncurses5; fileToCheckFor = "libtinfo.so.5"; }
+        ];
+      };
+      x86_64-linux = {
+        src = {
+          url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-deb10-linux.tar.xz";
+          sha256 = "0chnzy9j23b2wa8clx5arwz8wnjfxyjmz9qkj548z14cqf13slcl";
+        };
+        exePathForLibraryCheck = "ghc/stage2/build/tmp/ghc-stage2";
+        archSpecificLibraries = [
+          { nixPackage = ncurses6; fileToCheckFor = "libtinfo.so.6"; }
+        ];
+      };
+      armv7l-linux = {
+        src = {
+          url = "${downloadsUrl}/${version}/ghc-${version}-armv7-deb10-linux.tar.xz";
+          sha256 = "1j41cq5d3rmlgz7hzw8f908fs79gc5mn3q5wz277lk8zdf19g75v";
+        };
+        exePathForLibraryCheck = "ghc/stage2/build/tmp/ghc-stage2";
+        archSpecificLibraries = [
+          { nixPackage = ncurses6; fileToCheckFor = "libtinfo.so.6"; }
+        ];
+      };
+      aarch64-linux = {
+        src = {
+          url = "${downloadsUrl}/${version}/ghc-${version}-aarch64-deb10-linux.tar.xz";
+          sha256 = "14smwl3741ixnbgi0l51a7kh7xjkiannfqx15b72svky0y4l3wjw";
+        };
+        exePathForLibraryCheck = "ghc/stage2/build/tmp/ghc-stage2";
+        archSpecificLibraries = [
+          { nixPackage = ncurses6; fileToCheckFor = "libtinfo.so.6"; }
+          { nixPackage = numactl; fileToCheckFor = null; }
+        ];
+      };
+      x86_64-darwin = {
+        src = {
+          url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-apple-darwin.tar.xz";
+          sha256 = "1hngyq14l4f950hzhh2d204ca2gfc98pc9xdasxihzqd1jq75dzd";
+        };
+        exePathForLibraryCheck = null; # we don't have a library check for darwin yet
+        archSpecificLibraries = [
+          { nixPackage = ncurses6; fileToCheckFor = null; }
+          { nixPackage = libiconv; fileToCheckFor = null; }
+        ];
+      };
+    };
+    # Binary distributions for the musl libc for the respective system.
+    musl = {
+      x86_64-linux = {
+        src = {
+          url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-alpine3.10-linux-integer-simple.tar.xz";
+          sha256 = "0xpcbyaxqyhbl6f0i3s4rp2jm67nqpkfh2qlbj3i2fiaix89ml0l";
+        };
+        exePathForLibraryCheck = "bin/ghc";
+        archSpecificLibraries = [
+          # In contrast to glibc builds, the musl-bindist uses `libncursesw.so.*`
+          # instead of `libtinfo.so.*.`
+          { nixPackage = ncurses6; fileToCheckFor = "libncursesw.so.6"; }
+        ];
+      };
+    };
+  };
+
+  distSetName = if stdenv.hostPlatform.isMusl then "musl" else "defaultLibc";
+
+  binDistUsed = ghcBinDists.${distSetName}.${stdenv.hostPlatform.system}
+    or (throw "cannot bootstrap GHC on this platform ('${stdenv.hostPlatform.system}' with libc '${distSetName}')");
+
   useLLVM = !stdenv.targetPlatform.isx86;
 
-  libPath = lib.makeLibraryPath ([
-    ncurses6 gmp
-  ] ++ lib.optional (stdenv.hostPlatform.isDarwin) libiconv
-    ++ lib.optional (stdenv.hostPlatform.isAarch64) numactl);
+  libPath =
+    lib.makeLibraryPath (
+      [
+        gmp
+      ]
+      # Add arch-specific libraries.
+      ++ map ({ nixPackage, ... }: nixPackage) binDistUsed.archSpecificLibraries
+    );
 
   libEnvVar = lib.optionalString stdenv.hostPlatform.isDarwin "DY"
     + "LD_LIBRARY_PATH";
 
-  glibcDynLinker = assert stdenv.isLinux;
-    if stdenv.hostPlatform.libc == "glibc" then
-       # Could be stdenv.cc.bintools.dynamicLinker, keeping as-is to avoid rebuild.
-       ''"$(cat $NIX_CC/nix-support/dynamic-linker)"''
-    else
-      "${lib.getLib glibc}/lib/ld-linux*";
-
-  downloadsUrl = "https://downloads.haskell.org/ghc";
-
 in
 
 stdenv.mkDerivation rec {
-  version = "8.10.2";
+  inherit version;
 
   name = "ghc-${version}-binary";
 
-  # https://downloads.haskell.org/~ghc/8.10.2/
-  src = fetchurl ({
-    i686-linux = {
-      url = "${downloadsUrl}/${version}/ghc-${version}-i386-deb9-linux.tar.xz";
-      sha256 = "0bvwisl4w0z5z8z0da10m9sv0mhm9na2qm43qxr8zl23mn32mblx";
-    };
-    x86_64-linux = {
-      url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-deb10-linux.tar.xz";
-      sha256 = "0chnzy9j23b2wa8clx5arwz8wnjfxyjmz9qkj548z14cqf13slcl";
-    };
-    armv7l-linux = {
-      url = "${downloadsUrl}/${version}/ghc-${version}-armv7-deb10-linux.tar.xz";
-      sha256 = "1j41cq5d3rmlgz7hzw8f908fs79gc5mn3q5wz277lk8zdf19g75v";
-    };
-    aarch64-linux = {
-      url = "${downloadsUrl}/${version}/ghc-${version}-aarch64-deb10-linux.tar.xz";
-      sha256 = "14smwl3741ixnbgi0l51a7kh7xjkiannfqx15b72svky0y4l3wjw";
-    };
-    x86_64-darwin = {
-      url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-apple-darwin.tar.xz";
-      sha256 = "1hngyq14l4f950hzhh2d204ca2gfc98pc9xdasxihzqd1jq75dzd";
-    };
-  }.${stdenv.hostPlatform.system}
-    or (throw "cannot bootstrap GHC on this platform"));
+  src = fetchurl binDistUsed.src;
 
   nativeBuildInputs = [ perl ];
-  propagatedBuildInputs = lib.optionals useLLVM [ llvmPackages.llvm ];
+  propagatedBuildInputs =
+    lib.optionals useLLVM [ llvmPackages.llvm ]
+    # Because musl bindists currently provide no way to tell where
+    # libgmp is (see not [musl bindists have no .buildinfo]), we need
+    # to propagate `gmp`, otherwise programs built by this ghc will
+    # fail linking with `cannot find -lgmp` errors.
+    # Also, as of writing, the release pages of musl bindists claim
+    # that they use `integer-simple` and do not require `gmp`; however
+    # that is incorrect, so `gmp` is required until a release has been
+    # made that includes https://gitlab.haskell.org/ghc/ghc/-/issues/20059.
+    # (Note that for packaging the `-binary` compiler, nixpkgs does not care
+    # about whether or not `gmp` is used; this comment is just here to explain
+    # why the `gmp` dependency exists despite what the release page says.)
+    ++ lib.optionals stdenv.hostPlatform.isMusl [ gmp ]; # musl bindist needs this
 
+  # Set LD_LIBRARY_PATH or equivalent so that the programs running as part
+  # of the bindist installer can find the libraries they expect.
   # Cannot patchelf beforehand due to relative RPATHs that anticipate
-  # the final install location/
+  # the final install location.
   ${libEnvVar} = libPath;
 
   postUnpack =
+    # Verify our assumptions of which `libtinfo.so` (ncurses) version is used,
+    # so that we know when ghc bindists upgrade that and we need to update the
+    # version used in `libPath`.
+    lib.optionalString
+      (binDistUsed.exePathForLibraryCheck != null)
+      # Note the `*` glob because some GHCs have a suffix when unpacked, e.g.
+      # the musl bindist has dir `ghc-VERSION-x86_64-unknown-linux/`.
+      # As a result, don't shell-quote this glob when splicing the string.
+      (let buildExeGlob = ''ghc-${version}*/"${binDistUsed.exePathForLibraryCheck}"''; in
+        lib.concatStringsSep "\n" [
+          (''
+            echo "Checking that ghc binary exists in bindist at ${buildExeGlob}"
+            if ! test -e ${buildExeGlob}; then
+              echo >&2 "GHC binary ${binDistUsed.exePathForLibraryCheck} could not be found in the bindist build directory (at ${buildExeGlob}) for arch ${stdenv.hostPlatform.system}, please check that ghcBinDists correctly reflect the bindist dependencies!"; exit 1;
+            fi
+          '')
+          (lib.concatMapStringsSep
+            "\n"
+            ({ fileToCheckFor, nixPackage }:
+              lib.optionalString (fileToCheckFor != null) ''
+                echo "Checking bindist for ${fileToCheckFor} to ensure that is still used"
+                if ! readelf -d ${buildExeGlob} | grep "${fileToCheckFor}"; then
+                  echo >&2 "File ${fileToCheckFor} could not be found in ${binDistUsed.exePathForLibraryCheck} for arch ${stdenv.hostPlatform.system}, please check that ghcBinDists correctly reflect the bindist dependencies!"; exit 1;
+                fi
+
+                echo "Checking that the nix package ${nixPackage} contains ${fileToCheckFor}"
+                if ! test -e "${lib.getLib nixPackage}/lib/${fileToCheckFor}"; then
+                  echo >&2 "Nix package ${nixPackage} did not contain ${fileToCheckFor} for arch ${stdenv.hostPlatform.system}, please check that ghcBinDists correctly reflect the bindist dependencies!"; exit 1;
+                fi
+              ''
+            )
+            binDistUsed.archSpecificLibraries
+          )
+        ])
     # GHC has dtrace probes, which causes ld to try to open /usr/lib/libdtrace.dylib
     # during linking
-    lib.optionalString stdenv.isDarwin ''
+    + lib.optionalString stdenv.isDarwin ''
       export NIX_LDFLAGS+=" -no_dtrace_dof"
       # not enough room in the object files for the full path to libiconv :(
       for exe in $(find . -type f -executable); do
@@ -91,6 +215,9 @@ stdenv.mkDerivation rec {
       patchShebangs ghc-${version}/configure
     '' +
     # We have to patch the GMP paths for the integer-gmp package.
+    # Note [musl bindists have no .buildinfo]
+    # Note that musl bindists do not contain them; unclear if that's intended;
+    # see: https://gitlab.haskell.org/ghc/ghc/-/issues/20073#note_363231
     ''
       find . -name integer-gmp.buildinfo \
           -exec sed -i "s@extra-lib-dirs: @extra-lib-dirs: ${gmp.out}/lib@" {} \;
@@ -106,21 +233,8 @@ stdenv.mkDerivation rec {
     '' +
     # Rename needed libraries and binaries, fix interpreter
     lib.optionalString stdenv.isLinux ''
-      find . -type f -perm -0100 -exec patchelf \
-          --replace-needed libncurses${lib.optionalString stdenv.is64bit "w"}.so.6 libncurses.so \
-          --interpreter ${glibcDynLinker} {} \;
-
-      sed -i "s|/usr/bin/perl|perl\x00        |" ghc-${version}/ghc/stage2/build/tmp/ghc-stage2
-      sed -i "s|/usr/bin/gcc|gcc\x00        |" ghc-${version}/ghc/stage2/build/tmp/ghc-stage2
-    '' +
-    # We're kludging a glibc bindist into working with non-glibc...
-    # Here we patch up the use of `__strdup` (part of glibc binary ABI)
-    # to instead use `strdup` since musl doesn't provide __strdup
-    # (`__strdup` is defined to be an alias of `strdup` anyway[1]).
-    # [1] http://refspecs.linuxbase.org/LSB_4.0.0/LSB-Core-generic/LSB-Core-generic/baselib---strdup-1.html
-    # Use objcopy magic to make the change:
-    lib.optionalString stdenv.hostPlatform.isMusl ''
-      find ./ghc-${version}/rts -name "libHSrts*.a" -exec ''${OBJCOPY:-objcopy} --redefine-sym __strdup=strdup {} \;
+      find . -type f -executable -exec patchelf \
+          --interpreter ${stdenv.cc.bintools.dynamicLinker} {} \;
     '';
 
   # fix for `configure: error: Your linker is affected by binutils #16177`
@@ -130,15 +244,33 @@ stdenv.mkDerivation rec {
 
   configurePlatforms = [ ];
   configureFlags = [
-    "--with-gmp-libraries=${lib.getLib gmp}/lib"
     "--with-gmp-includes=${lib.getDev gmp}/include"
+    # Note `--with-gmp-libraries` does nothing for GHC bindists:
+    # https://gitlab.haskell.org/ghc/ghc/-/merge_requests/6124
   ] ++ lib.optional stdenv.isDarwin "--with-gcc=${./gcc-clang-wrapper.sh}"
+    # From: https://github.com/NixOS/nixpkgs/pull/43369/commits
     ++ lib.optional stdenv.hostPlatform.isMusl "--disable-ld-override";
 
   # No building is necessary, but calling make without flags ironically
   # calls install-strip ...
   dontBuild = true;
 
+  # Apparently necessary for the ghc Alpine (musl) bindist:
+  # When we strip, and then run the
+  #     patchelf --set-rpath "${libPath}:$(patchelf --print-rpath $p)" $p
+  # below, running ghc (e.g. during `installCheckPhase)` gives some apparently
+  # corrupted rpath or whatever makes the loader work on nonsensical strings:
+  #     running install tests
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: : symbol not found
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: ir6zf6c9f86pfx8sr30n2vjy-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/../lib/x86_64-linux-ghc-8.10.5/libHSexceptions-0.10.4-ghc8.10.5.so: symbol not found
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: y/lib/ghc-8.10.5/bin/../lib/x86_64-linux-ghc-8.10.5/libHStemplate-haskell-2.16.0.0-ghc8.10.5.so: symbol not found
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: 8.10.5/libHStemplate-haskell-2.16.0.0-ghc8.10.5.so: symbol not found
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: �: symbol not found
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: �?: symbol not found
+  #     Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: 64-linux-ghc-8.10.5/libHSexceptions-0.10.4-ghc8.10.5.so: symbol not found
+  # This is extremely bogus and should be investigated.
+  dontStrip = if stdenv.hostPlatform.isMusl then true else false; # `if` for explicitness
+
   # On Linux, use patchelf to modify the executables so that they can
   # find editline/gmp.
   postFixup = lib.optionalString stdenv.isLinux
@@ -186,13 +318,23 @@ stdenv.mkDerivation rec {
     find $out -type f -name '*.p_o' -delete
     find $out -type f -name '*.p_hi' -delete
     find $out -type f -name '*_p.a' -delete
-    rm $out/lib/ghc-*/bin/ghc-iserv-prof
+    # `-f` because e.g. musl bindist does not have this file.
+    rm -f $out/lib/ghc-*/bin/ghc-iserv-prof
     # Hydra will redistribute this derivation, so we have to keep the docs for
     # legal reasons (retaining the legal notices etc)
     # As a last resort we could unpack the docs separately and symlink them in.
     # They're in $out/share/{doc,man}.
   '';
 
+  # In nixpkgs, musl based builds currently enable `pie` hardening by default
+  # (see `defaultHardeningFlags` in `make-derivation.nix`).
+  # But GHC cannot currently produce outputs that are ready for `-pie` linking.
+  # Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
+  # See:
+  # * https://github.com/NixOS/nixpkgs/issues/129247
+  # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
+  hardeningDisable = lib.optional stdenv.targetPlatform.isMusl "pie";
+
   doInstallCheck = true;
   installCheckPhase = ''
     unset ${libEnvVar}
@@ -221,7 +363,16 @@ stdenv.mkDerivation rec {
     homepage = "http://haskell.org/ghc";
     description = "The Glasgow Haskell Compiler";
     license = lib.licenses.bsd3;
-    platforms = ["x86_64-linux" "armv7l-linux" "aarch64-linux" "i686-linux" "x86_64-darwin"];
+    # HACK: since we can't encode the libc / abi in platforms, we need
+    # to make the platform list dependent on the evaluation platform
+    # in order to avoid eval errors with musl which supports less
+    # platforms than the default libcs (i. e. glibc / libSystem).
+    # This is done for the benefit of Hydra, so `packagePlatforms`
+    # won't return any platforms that would cause an evaluation
+    # failure for `pkgsMusl.haskell.compiler.ghc8102Binary`, as
+    # long as the evaluator runs on a platform that supports
+    # `pkgsMusl`.
+    platforms = builtins.attrNames ghcBinDists.${distSetName};
     hydraPlatforms = builtins.filter (p: minimal || p != "aarch64-linux") platforms;
     maintainers = with lib.maintainers; [ lostnet ];
   };
diff --git a/pkgs/development/compilers/ghc/8.10.4.nix b/pkgs/development/compilers/ghc/8.10.4.nix
index f007dcf7898..10ca2f6662c 100644
--- a/pkgs/development/compilers/ghc/8.10.4.nix
+++ b/pkgs/development/compilers/ghc/8.10.4.nix
@@ -38,6 +38,20 @@
   ghcFlavour ? lib.optionalString (stdenv.targetPlatform != stdenv.hostPlatform)
     (if useLLVM then "perf-cross" else "perf-cross-ncg")
 
+, #  Whether to build sphinx documentation.
+  enableDocs ? (
+    # Docs disabled for musl and cross because it's a large task to keep
+    # all `sphinx` dependencies building in those environments.
+    # `sphinx` pulls in among others:
+    # Ruby, Python, Perl, Rust, OpenGL, Xorg, gtk, LLVM.
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+    && !stdenv.hostPlatform.isMusl
+  )
+
+, enableHaddockProgram ?
+    # Disabled for cross; see note [HADDOCK_DOCS].
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+
 , # Whether to disable the large address space allocator
   # necessary fix for iOS: https://www.reddit.com/r/haskell/comments/4ttdz1/building_an_osxi386_to_iosarm64_cross_compiler/d5qvd67/
   disableLargeAddressSpace ? stdenv.targetPlatform.isDarwin && stdenv.targetPlatform.isAarch64
@@ -45,6 +59,10 @@
 
 assert !enableIntegerSimple -> gmp != null;
 
+# Cross cannot currently build the `haddock` program for silly reasons,
+# see note [HADDOCK_DOCS].
+assert (stdenv.targetPlatform != stdenv.hostPlatform) -> !enableHaddockProgram;
+
 let
   inherit (stdenv) buildPlatform hostPlatform targetPlatform;
 
@@ -60,14 +78,26 @@ let
     ifneq \"\$(BuildFlavour)\" \"\"
     include mk/flavours/\$(BuildFlavour).mk
     endif
+    BUILD_SPHINX_HTML = ${if enableDocs then "YES" else "NO"}
+    BUILD_SPHINX_PDF = NO
+  '' +
+  # Note [HADDOCK_DOCS]:
+  # Unfortunately currently `HADDOCK_DOCS` controls both whether the `haddock`
+  # program is built (which we generally always want to have a complete GHC install)
+  # and whether it is run on the GHC sources to generate hyperlinked source code
+  # (which is impossible for cross-compilation); see:
+  # https://gitlab.haskell.org/ghc/ghc/-/issues/20077
+  # This implies that currently a cross-compiled GHC will never have a `haddock`
+  # program, so it can never generate haddocks for any packages.
+  # If this is solved in the future, we'd like to unconditionally
+  # build the haddock program (removing the `enableHaddockProgram` option).
+  ''
+    HADDOCK_DOCS = ${if enableHaddockProgram then "YES" else "NO"}
     DYNAMIC_GHC_PROGRAMS = ${if enableShared then "YES" else "NO"}
     INTEGER_LIBRARY = ${if enableIntegerSimple then "integer-simple" else "integer-gmp"}
   '' + lib.optionalString (targetPlatform != hostPlatform) ''
     Stage1Only = ${if targetPlatform.system == hostPlatform.system then "NO" else "YES"}
     CrossCompilePrefix = ${targetPrefix}
-    HADDOCK_DOCS = NO
-    BUILD_SPHINX_HTML = NO
-    BUILD_SPHINX_PDF = NO
   '' + lib.optionalString (!enableProfiledLibs) ''
     GhcLibWays = "v dyn"
   '' + lib.optionalString enableRelocatedStaticLibs ''
@@ -217,8 +247,10 @@ stdenv.mkDerivation (rec {
   dontAddExtraLibs = true;
 
   nativeBuildInputs = [
-    perl autoconf automake m4 python3 sphinx
+    perl autoconf automake m4 python3
     ghc bootPkgs.alex bootPkgs.happy bootPkgs.hscolour
+  ] ++ lib.optionals enableDocs [
+    sphinx
   ];
 
   # For building runtime libs
@@ -238,7 +270,16 @@ stdenv.mkDerivation (rec {
 
   checkTarget = "test";
 
-  hardeningDisable = [ "format" ] ++ lib.optional stdenv.targetPlatform.isMusl "pie";
+  hardeningDisable =
+    [ "format" ]
+    # In nixpkgs, musl based builds currently enable `pie` hardening by default
+    # (see `defaultHardeningFlags` in `make-derivation.nix`).
+    # But GHC cannot currently produce outputs that are ready for `-pie` linking.
+    # Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
+    # See:
+    # * https://github.com/NixOS/nixpkgs/issues/129247
+    # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
+    ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
   postInstall = ''
     # Install the bash completion file.
diff --git a/pkgs/development/compilers/ghc/8.6.5-binary.nix b/pkgs/development/compilers/ghc/8.6.5-binary.nix
index 8a0994b8b6a..c3d6ab1beca 100644
--- a/pkgs/development/compilers/ghc/8.6.5-binary.nix
+++ b/pkgs/development/compilers/ghc/8.6.5-binary.nix
@@ -121,8 +121,9 @@ stdenv.mkDerivation rec {
 
   configurePlatforms = [ ];
   configureFlags = [
-    "--with-gmp-libraries=${lib.getLib gmp}/lib"
     "--with-gmp-includes=${lib.getDev gmp}/include"
+    # Note `--with-gmp-libraries` does nothing for GHC bindists:
+    # https://gitlab.haskell.org/ghc/ghc/-/merge_requests/6124
   ] ++ lib.optional stdenv.isDarwin "--with-gcc=${./gcc-clang-wrapper.sh}"
     ++ lib.optional stdenv.hostPlatform.isMusl "--disable-ld-override";
 
@@ -152,6 +153,15 @@ stdenv.mkDerivation rec {
     done
   '';
 
+  # In nixpkgs, musl based builds currently enable `pie` hardening by default
+  # (see `defaultHardeningFlags` in `make-derivation.nix`).
+  # But GHC cannot currently produce outputs that are ready for `-pie` linking.
+  # Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
+  # See:
+  # * https://github.com/NixOS/nixpkgs/issues/129247
+  # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
+  hardeningDisable = lib.optional stdenv.targetPlatform.isMusl "pie";
+
   doInstallCheck = true;
   installCheckPhase = ''
     unset ${libEnvVar}
diff --git a/pkgs/development/compilers/ghc/8.8.4.nix b/pkgs/development/compilers/ghc/8.8.4.nix
index 544b96f5e4f..23826614716 100644
--- a/pkgs/development/compilers/ghc/8.8.4.nix
+++ b/pkgs/development/compilers/ghc/8.8.4.nix
@@ -38,6 +38,20 @@
   ghcFlavour ? lib.optionalString (stdenv.targetPlatform != stdenv.hostPlatform)
     (if useLLVM then "perf-cross" else "perf-cross-ncg")
 
+, #  Whether to build sphinx documentation.
+  enableDocs ? (
+    # Docs disabled for musl and cross because it's a large task to keep
+    # all `sphinx` dependencies building in those environments.
+    # `sphinx` pullls in among others:
+    # Ruby, Python, Perl, Rust, OpenGL, Xorg, gtk, LLVM.
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+    && !stdenv.hostPlatform.isMusl
+  )
+
+, enableHaddockProgram ?
+    # Disabled for cross; see note [HADDOCK_DOCS].
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+
 , # Whether to disable the large address space allocator
   # necessary fix for iOS: https://www.reddit.com/r/haskell/comments/4ttdz1/building_an_osxi386_to_iosarm64_cross_compiler/d5qvd67/
   disableLargeAddressSpace ? stdenv.targetPlatform.isDarwin && stdenv.targetPlatform.isAarch64
@@ -45,6 +59,10 @@
 
 assert !enableIntegerSimple -> gmp != null;
 
+# Cross cannot currently build the `haddock` program for silly reasons,
+# see note [HADDOCK_DOCS].
+assert (stdenv.targetPlatform != stdenv.hostPlatform) -> !enableHaddockProgram;
+
 let
   inherit (stdenv) buildPlatform hostPlatform targetPlatform;
 
@@ -60,6 +78,21 @@ let
     ifneq \"\$(BuildFlavour)\" \"\"
     include mk/flavours/\$(BuildFlavour).mk
     endif
+    BUILD_SPHINX_HTML = ${if enableDocs then "YES" else "NO"}
+    BUILD_SPHINX_PDF = NO
+  '' +
+  # Note [HADDOCK_DOCS]:
+  # Unfortunately currently `HADDOCK_DOCS` controls both whether the `haddock`
+  # program is built (which we generally always want to have a complete GHC install)
+  # and whether it is run on the GHC sources to generate hyperlinked source code
+  # (which is impossible for cross-compilation); see:
+  # https://gitlab.haskell.org/ghc/ghc/-/issues/20077
+  # This implies that currently a cross-compiled GHC will never have a `haddock`
+  # program, so it can never generate haddocks for any packages.
+  # If this is solved in the future, we'd like to unconditionally
+  # build the haddock program (removing the `enableHaddockProgram` option).
+  ''
+    HADDOCK_DOCS = ${if enableHaddockProgram then "YES" else "NO"}
     DYNAMIC_GHC_PROGRAMS = ${if enableShared then "YES" else "NO"}
     INTEGER_LIBRARY = ${if enableIntegerSimple then "integer-simple" else "integer-gmp"}
   ''
@@ -72,9 +105,6 @@ let
   + lib.optionalString (targetPlatform != hostPlatform) ''
     Stage1Only = ${if (targetPlatform.system == hostPlatform.system && !targetPlatform.isiOS) then "NO" else "YES"}
     CrossCompilePrefix = ${targetPrefix}
-    HADDOCK_DOCS = NO
-    BUILD_SPHINX_HTML = NO
-    BUILD_SPHINX_PDF = NO
   '' + lib.optionalString dontStrip ''
     STRIP_CMD = :
   '' + lib.optionalString (!enableProfiledLibs) ''
@@ -142,11 +172,14 @@ stdenv.mkDerivation (rec {
   postPatch = "patchShebangs .";
 
   # GHC is a bit confused on its cross terminology.
-  preConfigure = lib.optionalString stdenv.isAarch64 ''
+  preConfigure =
     # Aarch64 allow backward bootstrapping since earlier versions are unstable.
-    find . -name \*\.cabal\* -exec sed -i -e 's/\(base.*\)4.14/\14.16/' {} \; \
-      -exec sed -i -e 's/\(prim.*\)0.6/\10.8/' {} \;
-  '' + ''
+    # Same for musl, as earlier versions do not provide a musl bindist for bootstrapping.
+    lib.optionalString (stdenv.isAarch64 || stdenv.hostPlatform.isMusl) ''
+      find . -name \*\.cabal\* -exec sed -i -e 's/\(base.*\)4.14/\14.16/' {} \; \
+        -exec sed -i -e 's/\(prim.*\)0.6/\10.8/' {} \;
+    ''
+  + ''
     for env in $(env | grep '^TARGET_' | sed -E 's|\+?=.*||'); do
       export "''${env#TARGET_}=''${!env}"
     done
@@ -224,8 +257,10 @@ stdenv.mkDerivation (rec {
   dontAddExtraLibs = true;
 
   nativeBuildInputs = [
-    perl autoconf automake m4 python3 sphinx
+    perl autoconf automake m4 python3
     ghc bootPkgs.alex bootPkgs.happy bootPkgs.hscolour
+  ] ++ lib.optionals enableDocs [
+    sphinx
   ];
 
   # For building runtime libs
@@ -245,7 +280,16 @@ stdenv.mkDerivation (rec {
 
   checkTarget = "test";
 
-  hardeningDisable = [ "format" ] ++ lib.optional stdenv.targetPlatform.isMusl "pie";
+  hardeningDisable =
+    [ "format" ]
+    # In nixpkgs, musl based builds currently enable `pie` hardening by default
+    # (see `defaultHardeningFlags` in `make-derivation.nix`).
+    # But GHC cannot currently produce outputs that are ready for `-pie` linking.
+    # Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
+    # See:
+    # * https://github.com/NixOS/nixpkgs/issues/129247
+    # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
+    ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
   postInstall = ''
     # Install the bash completion file.
diff --git a/pkgs/development/compilers/ghc/9.0.1.nix b/pkgs/development/compilers/ghc/9.0.1.nix
index f5a6b5f32fa..d2ae51c66de 100644
--- a/pkgs/development/compilers/ghc/9.0.1.nix
+++ b/pkgs/development/compilers/ghc/9.0.1.nix
@@ -39,6 +39,20 @@
   ghcFlavour ? lib.optionalString (stdenv.targetPlatform != stdenv.hostPlatform)
     (if useLLVM then "perf-cross" else "perf-cross-ncg")
 
+, #  Whether to build sphinx documentation.
+  enableDocs ? (
+    # Docs disabled for musl and cross because it's a large task to keep
+    # all `sphinx` dependencies building in those environments.
+    # `sphinx` pullls in among others:
+    # Ruby, Python, Perl, Rust, OpenGL, Xorg, gtk, LLVM.
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+    && !stdenv.hostPlatform.isMusl
+  )
+
+, enableHaddockProgram ?
+    # Disabled for cross; see note [HADDOCK_DOCS].
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+
 , # Whether to disable the large address space allocator
   # necessary fix for iOS: https://www.reddit.com/r/haskell/comments/4ttdz1/building_an_osxi386_to_iosarm64_cross_compiler/d5qvd67/
   disableLargeAddressSpace ? stdenv.targetPlatform.isDarwin && stdenv.targetPlatform.isAarch64
@@ -46,6 +60,10 @@
 
 assert !enableIntegerSimple -> gmp != null;
 
+# Cross cannot currently build the `haddock` program for silly reasons,
+# see note [HADDOCK_DOCS].
+assert (stdenv.targetPlatform != stdenv.hostPlatform) -> !enableHaddockProgram;
+
 let
   inherit (stdenv) buildPlatform hostPlatform targetPlatform;
 
@@ -61,14 +79,26 @@ let
     ifneq \"\$(BuildFlavour)\" \"\"
     include mk/flavours/\$(BuildFlavour).mk
     endif
+    BUILD_SPHINX_HTML = ${if enableDocs then "YES" else "NO"}
+    BUILD_SPHINX_PDF = NO
+  '' +
+  # Note [HADDOCK_DOCS]:
+  # Unfortunately currently `HADDOCK_DOCS` controls both whether the `haddock`
+  # program is built (which we generally always want to have a complete GHC install)
+  # and whether it is run on the GHC sources to generate hyperlinked source code
+  # (which is impossible for cross-compilation); see:
+  # https://gitlab.haskell.org/ghc/ghc/-/issues/20077
+  # This implies that currently a cross-compiled GHC will never have a `haddock`
+  # program, so it can never generate haddocks for any packages.
+  # If this is solved in the future, we'd like to unconditionally
+  # build the haddock program (removing the `enableHaddockProgram` option).
+  ''
+    HADDOCK_DOCS = ${if enableHaddockProgram then "YES" else "NO"}
     DYNAMIC_GHC_PROGRAMS = ${if enableShared then "YES" else "NO"}
     INTEGER_LIBRARY = ${if enableIntegerSimple then "integer-simple" else "integer-gmp"}
   '' + lib.optionalString (targetPlatform != hostPlatform) ''
     Stage1Only = ${if targetPlatform.system == hostPlatform.system then "NO" else "YES"}
     CrossCompilePrefix = ${targetPrefix}
-    HADDOCK_DOCS = NO
-    BUILD_SPHINX_HTML = NO
-    BUILD_SPHINX_PDF = NO
   '' + lib.optionalString (!enableProfiledLibs) ''
     GhcLibWays = "v dyn"
   '' + lib.optionalString enableRelocatedStaticLibs ''
@@ -143,7 +173,7 @@ stdenv.mkDerivation (rec {
 
     echo -n "${buildMK}" > mk/build.mk
     sed -i -e 's|-isysroot /Developer/SDKs/MacOSX10.5.sdk||' configure
-  '' + lib.optionalString (stdenv.isLinux) ''
+  '' + lib.optionalString (stdenv.isLinux && hostPlatform.libc == "glibc") ''
     export LOCALE_ARCHIVE="${glibcLocales}/lib/locale/locale-archive"
   '' + lib.optionalString (!stdenv.isDarwin) ''
     export NIX_LDFLAGS+=" -rpath $out/lib/ghc-${version}"
@@ -204,8 +234,10 @@ stdenv.mkDerivation (rec {
   dontAddExtraLibs = true;
 
   nativeBuildInputs = [
-    perl autoconf automake m4 python3 sphinx
+    perl autoconf automake m4 python3
     ghc bootPkgs.alex bootPkgs.happy bootPkgs.hscolour
+  ] ++ lib.optionals enableDocs [
+    sphinx
   ];
 
   # For building runtime libs
@@ -225,7 +257,16 @@ stdenv.mkDerivation (rec {
 
   checkTarget = "test";
 
-  hardeningDisable = [ "format" ] ++ lib.optional stdenv.targetPlatform.isMusl "pie";
+  hardeningDisable =
+    [ "format" ]
+    # In nixpkgs, musl based builds currently enable `pie` hardening by default
+    # (see `defaultHardeningFlags` in `make-derivation.nix`).
+    # But GHC cannot currently produce outputs that are ready for `-pie` linking.
+    # Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
+    # See:
+    # * https://github.com/NixOS/nixpkgs/issues/129247
+    # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
+    ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
   postInstall = ''
     # Install the bash completion file.
diff --git a/pkgs/development/compilers/ghc/head.nix b/pkgs/development/compilers/ghc/head.nix
index ec236731afd..2ea14b78cc4 100644
--- a/pkgs/development/compilers/ghc/head.nix
+++ b/pkgs/development/compilers/ghc/head.nix
@@ -46,6 +46,20 @@
   ghcFlavour ? lib.optionalString (stdenv.targetPlatform != stdenv.hostPlatform)
     (if useLLVM then "perf-cross" else "perf-cross-ncg")
 
+, #  Whether to build sphinx documentation.
+  enableDocs ? (
+    # Docs disabled for musl and cross because it's a large task to keep
+    # all `sphinx` dependencies building in those environments.
+    # `sphinx` pullls in among others:
+    # Ruby, Python, Perl, Rust, OpenGL, Xorg, gtk, LLVM.
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+    && !stdenv.hostPlatform.isMusl
+  )
+
+, enableHaddockProgram ?
+    # Disabled for cross; see note [HADDOCK_DOCS].
+    (stdenv.targetPlatform == stdenv.hostPlatform)
+
 , # Whether to disable the large address space allocator
   # necessary fix for iOS: https://www.reddit.com/r/haskell/comments/4ttdz1/building_an_osxi386_to_iosarm64_cross_compiler/d5qvd67/
   disableLargeAddressSpace ? stdenv.targetPlatform.isDarwin && stdenv.targetPlatform.isAarch64
@@ -53,6 +67,10 @@
 
 assert !enableNativeBignum -> gmp != null;
 
+# Cross cannot currently build the `haddock` program for silly reasons,
+# see note [HADDOCK_DOCS].
+assert (stdenv.targetPlatform != stdenv.hostPlatform) -> !enableHaddockProgram;
+
 let
   inherit (stdenv) buildPlatform hostPlatform targetPlatform;
 
@@ -68,14 +86,26 @@ let
     ifneq \"\$(BuildFlavour)\" \"\"
     include mk/flavours/\$(BuildFlavour).mk
     endif
+    BUILD_SPHINX_HTML = ${if enableDocs then "YES" else "NO"}
+    BUILD_SPHINX_PDF = NO
+  '' +
+  # Note [HADDOCK_DOCS]:
+  # Unfortunately currently `HADDOCK_DOCS` controls both whether the `haddock`
+  # program is built (which we generally always want to have a complete GHC install)
+  # and whether it is run on the GHC sources to generate hyperlinked source code
+  # (which is impossible for cross-compilation); see:
+  # https://gitlab.haskell.org/ghc/ghc/-/issues/20077
+  # This implies that currently a cross-compiled GHC will never have a `haddock`
+  # program, so it can never generate haddocks for any packages.
+  # If this is solved in the future, we'd like to unconditionally
+  # build the haddock program (removing the `enableHaddockProgram` option).
+  ''
+    HADDOCK_DOCS = ${if enableHaddockProgram then "YES" else "NO"}
     DYNAMIC_GHC_PROGRAMS = ${if enableShared then "YES" else "NO"}
     BIGNUM_BACKEND = ${if enableNativeBignum then "native" else "gmp"}
   '' + lib.optionalString (targetPlatform != hostPlatform) ''
     Stage1Only = ${if (targetPlatform.system == hostPlatform.system && !targetPlatform.isiOS) then "NO" else "YES"}
     CrossCompilePrefix = ${targetPrefix}
-    HADDOCK_DOCS = NO
-    BUILD_SPHINX_HTML = NO
-    BUILD_SPHINX_PDF = NO
   '' + lib.optionalString dontStrip ''
     STRIP_CMD = :
   '' + lib.optionalString (!enableProfiledLibs) ''
@@ -221,8 +251,10 @@ stdenv.mkDerivation (rec {
   dontAddExtraLibs = true;
 
   nativeBuildInputs = [
-    perl autoconf autoreconfHook automake m4 python3 sphinx
+    perl autoconf autoreconfHook automake m4 python3
     ghc bootPkgs.alex bootPkgs.happy bootPkgs.hscolour
+  ] ++ lib.optionals enableDocs [
+    sphinx
   ];
 
   # For building runtime libs
@@ -242,7 +274,16 @@ stdenv.mkDerivation (rec {
 
   checkTarget = "test";
 
-  hardeningDisable = [ "format" ] ++ lib.optional stdenv.targetPlatform.isMusl "pie";
+  hardeningDisable =
+    [ "format" ]
+    # In nixpkgs, musl based builds currently enable `pie` hardening by default
+    # (see `defaultHardeningFlags` in `make-derivation.nix`).
+    # But GHC cannot currently produce outputs that are ready for `-pie` linking.
+    # Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
+    # See:
+    # * https://github.com/NixOS/nixpkgs/issues/129247
+    # * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
+    ++ lib.optional stdenv.targetPlatform.isMusl "pie";
 
   postInstall = ''
     # Install the bash completion file.