nixpkgs/pkgs/development/haskell-modules/with-packages-wrapper.nix
sternenseemann 456faf71e5 ghcWithPackages: use haskellCompilerName for ghclibdir
This is done for consistency with generic-builder.nix and because it's
easier for downstream users to replicate which will inevitably use our
code as inspiration.
2022-03-31 12:50:43 +02:00

184 lines
7.4 KiB
Nix

{ lib, stdenv, haskellPackages, symlinkJoin, makeWrapper
# GHC will have LLVM available if necessary for the respective target,
# so useLLVM only needs to be changed if -fllvm is to be used for a
# platform that has NCG support
, useLLVM ? false
, withHoogle ? false
, hoogleWithPackages
, postBuild ? ""
, ghcLibdir ? null # only used by ghcjs, when resolving plugins
}:
# This argument is a function which selects a list of Haskell packages from any
# passed Haskell package set.
#
# Example:
# (hpkgs: [ hpkgs.mtl hpkgs.lens ])
selectPackages:
# It's probably a good idea to include the library "ghc-paths" in the
# compiler environment, because we have a specially patched version of
# that package in Nix that honors these environment variables
#
# NIX_GHC
# NIX_GHCPKG
# NIX_GHC_DOCDIR
# NIX_GHC_LIBDIR
#
# instead of hard-coding the paths. The wrapper sets these variables
# appropriately to configure ghc-paths to point back to the wrapper
# instead of to the pristine GHC package, which doesn't know any of the
# additional libraries.
#
# A good way to import the environment set by the wrapper below into
# your shell is to add the following snippet to your ~/.bashrc:
#
# if [ -e ~/.nix-profile/bin/ghc ]; then
# eval $(grep export ~/.nix-profile/bin/ghc)
# fi
let
inherit (haskellPackages) llvmPackages ghc;
packages = selectPackages haskellPackages
++ lib.optional withHoogle (hoogleWithPackages selectPackages);
isGhcjs = ghc.isGhcjs or false;
isHaLVM = ghc.isHaLVM or false;
ghc761OrLater = isGhcjs || isHaLVM || lib.versionOlder "7.6.1" ghc.version;
packageDBFlag = if ghc761OrLater then "--global-package-db" else "--global-conf";
ghcCommand' = if isGhcjs then "ghcjs" else "ghc";
ghcCommand = "${ghc.targetPrefix}${ghcCommand'}";
ghcCommandCaps= lib.toUpper ghcCommand';
libDir = if isHaLVM then "$out/lib/HaLVM-${ghc.version}"
else "$out/lib/${ghc.targetPrefix}${ghc.haskellCompilerName}";
docDir = "$out/share/doc/ghc/html";
packageCfgDir = "${libDir}/package.conf.d";
paths = lib.filter (x: x ? isHaskellLibrary) (lib.closePropagation packages);
hasLibraries = lib.any (x: x.isHaskellLibrary) paths;
# CLang is needed on Darwin for -fllvm to work:
# https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/codegens.html#llvm-code-generator-fllvm
llvm = lib.makeBinPath
([ llvmPackages.llvm ]
++ lib.optional stdenv.targetPlatform.isDarwin llvmPackages.clang);
in
assert ghcLibdir != null -> (ghc.isGhcjs or false);
if paths == [] && !useLLVM then ghc else
symlinkJoin {
# this makes computing paths from the name attribute impossible;
# if such a feature is needed, the real compiler name should be saved
# as a dedicated drv attribute, like `compiler-name`
name = ghc.name + "-with-packages";
paths = paths ++ [ghc];
nativeBuildInputs = [ makeWrapper ];
postBuild = ''
# wrap compiler executables with correct env variables
for prg in ${ghcCommand} ${ghcCommand}i ${ghcCommand}-${ghc.version} ${ghcCommand}i-${ghc.version}; do
if [[ -x "${ghc}/bin/$prg" ]]; then
rm -f $out/bin/$prg
makeWrapper ${ghc}/bin/$prg $out/bin/$prg \
--add-flags '"-B$NIX_${ghcCommandCaps}_LIBDIR"' \
--set "NIX_${ghcCommandCaps}" "$out/bin/${ghcCommand}" \
--set "NIX_${ghcCommandCaps}PKG" "$out/bin/${ghcCommand}-pkg" \
--set "NIX_${ghcCommandCaps}_DOCDIR" "${docDir}" \
--set "NIX_${ghcCommandCaps}_LIBDIR" "${libDir}" \
${lib.optionalString (ghc.isGhcjs or false)
''--set NODE_PATH "${ghc.socket-io}/lib/node_modules"''
} \
${lib.optionalString useLLVM ''--prefix "PATH" ":" "${llvm}"''}
fi
done
for prg in runghc runhaskell; do
if [[ -x "${ghc}/bin/$prg" ]]; then
rm -f $out/bin/$prg
makeWrapper ${ghc}/bin/$prg $out/bin/$prg \
--add-flags "-f $out/bin/${ghcCommand}" \
--set "NIX_${ghcCommandCaps}" "$out/bin/${ghcCommand}" \
--set "NIX_${ghcCommandCaps}PKG" "$out/bin/${ghcCommand}-pkg" \
--set "NIX_${ghcCommandCaps}_DOCDIR" "${docDir}" \
--set "NIX_${ghcCommandCaps}_LIBDIR" "${libDir}"
fi
done
for prg in ${ghcCommand}-pkg ${ghcCommand}-pkg-${ghc.version}; do
if [[ -x "${ghc}/bin/$prg" ]]; then
rm -f $out/bin/$prg
makeWrapper ${ghc}/bin/$prg $out/bin/$prg --add-flags "${packageDBFlag}=${packageCfgDir}"
fi
done
# haddock was referring to the base ghc, https://github.com/NixOS/nixpkgs/issues/36976
if [[ -x "${ghc}/bin/haddock" ]]; then
rm -f $out/bin/haddock
makeWrapper ${ghc}/bin/haddock $out/bin/haddock \
--add-flags '"-B$NIX_${ghcCommandCaps}_LIBDIR"' \
--set "NIX_${ghcCommandCaps}_LIBDIR" "${libDir}"
fi
'' + (lib.optionalString (stdenv.targetPlatform.isDarwin && !isGhcjs && !stdenv.targetPlatform.isiOS) ''
# Work around a linker limit in macOS Sierra (see generic-builder.nix):
local packageConfDir="${packageCfgDir}";
local dynamicLinksDir="$out/lib/links"
mkdir -p $dynamicLinksDir
# Clean up the old links that may have been (transitively) included by
# symlinkJoin:
rm -f $dynamicLinksDir/*
for d in $(grep -Poz "dynamic-library-dirs:\s*\K .+\n" $packageConfDir/*|awk '{print $2}'|sort -u); do
ln -s $d/*.dylib $dynamicLinksDir
done
for f in $packageConfDir/*.conf; do
# Initially, $f is a symlink to a read-only file in one of the inputs
# (as a result of this symlinkJoin derivation).
# Replace it with a copy whose dynamic-library-dirs points to
# $dynamicLinksDir
cp $f $f-tmp
rm $f
sed "N;s,dynamic-library-dirs:\s*.*,dynamic-library-dirs: $dynamicLinksDir," $f-tmp > $f
rm $f-tmp
done
'') + ''
${lib.optionalString hasLibraries ''
# GHC 8.10 changes.
# Instead of replacing package.cache[.lock] with the new file,
# ghc-pkg is now trying to open the file. These file are symlink
# to another nix derivation, so they are not writable. Removing
# them allow the correct behavior of ghc-pkg recache
# See: https://github.com/NixOS/nixpkgs/issues/79441
rm ${packageCfgDir}/package.cache.lock
rm ${packageCfgDir}/package.cache
$out/bin/${ghcCommand}-pkg recache
''}
${# ghcjs will read the ghc_libdir file when resolving plugins.
lib.optionalString (isGhcjs && ghcLibdir != null) ''
mkdir -p "${libDir}"
rm -f "${libDir}/ghc_libdir"
printf '%s' '${ghcLibdir}' > "${libDir}/ghc_libdir"
''}
$out/bin/${ghcCommand}-pkg check
'' + postBuild;
passthru = {
preferLocalBuild = true;
inherit (ghc) version meta;
# Inform users about backwards incompatibilities with <= 21.05
override = _: throw ''
The ghc.withPackages wrapper itself can now be overridden, but no longer
the result of calling it (as before). Consequently overrides need to be
adjusted: Instead of
(ghc.withPackages (p: [ p.my-package ])).override { withLLLVM = true; }
use
(ghc.withPackages.override { useLLVM = true; }) (p: [ p.my-package ])
Also note that withLLVM has been renamed to useLLVM for consistency with
the GHC Nix expressions.'';
};
}