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{
lib,
stdenv,
fetchFromGitHub,
python3,
nodejs,
closurecompiler,
jre,
binaryen,
llvmPackages,
symlinkJoin,
makeWrapper,
replaceVars,
buildNpmPackage,
nix-update-script,
emscripten,
}:
let
pythonWithPsutil = python3.withPackages (ps: [ ps.psutil ]);
in
stdenv.mkDerivation rec {
pname = "emscripten";
version = "6.0.9";
llvmEnv = symlinkJoin {
name = "emscripten-llvm-${version}";
paths = with llvmPackages; [
clang-unwrapped
(lib.getLib clang-unwrapped)
lld
llvm
];
};
nodeModules = buildNpmPackage {
name = "emscripten-node-modules-${version}";
inherit pname version src;
npmDepsHash = "sha256-t0ekoKE9LQk6an4Sk51IOqKBOSmA7sbnoYLsOlsEZIo=";
dontBuild = true;
# Copy node_modules directly.
installPhase = ''
cp -r node_modules $out/
'';
};
src = fetchFromGitHub {
owner = "emscripten-core";
repo = "emscripten";
hash = "sha256-zfNbudFzII/nc0oyojalEaVppSWbCg7v1yiM7ENYQSE=";
rev = version;
};
strictDeps = true;
nativeBuildInputs = [
makeWrapper
python3
];
buildInputs = [
nodejs
];
patches = [
(replaceVars ./0001-emulate-clang-sysroot-include-logic.patch {
resourceDir = "${llvmEnv}/lib/clang/${lib.versions.major llvmPackages.llvm.version}/";
})
# Remove this patch when llvmPackages reaches LLVM 23
./0002-libunwind-restore-Unwind_CallPersonality.patch
];
buildPhase = ''
runHook preBuild
# Make Python scripts executable so patchShebangs will patch their shebangs
chmod +x *.py tools/*.py
patchShebangs .
# Emscripten requires an unreleased LLVM version. Set the check to the
# LLVM version that this package supplies. The --replace-fail flag stops
# the build if Emscripten changes this constant. A sed command for a
# fixed version does not give an error. It leaves the check at an LLVM
# version that this package does not have.
substituteInPlace tools/shared.py \
--replace-fail "EXPECTED_LLVM_VERSION = 24" \
"EXPECTED_LLVM_VERSION = ${lib.versions.major llvmPackages.llvm.version}"
# fixes cmake support
sed -i -e "s/print \('emcc (Emscript.*\)/sys.stderr.write(\1); sys.stderr.flush()/g" emcc.py
sed -i "/^def check_sanity/a\\ return" tools/shared.py
echo "EMSCRIPTEN_ROOT = '$out/share/emscripten'" > .emscripten
echo "LLVM_ROOT = '${llvmEnv}/bin'" >> .emscripten
echo "NODE_JS = '${nodejs}/bin/node'" >> .emscripten
echo "JS_ENGINES = [NODE_JS]" >> .emscripten
echo "CLOSURE_COMPILER = ['${closurecompiler}/bin/closure-compiler']" >> .emscripten
echo "JAVA = '${jre}/bin/java'" >> .emscripten
# to make the test(s) below work
# echo "SPIDERMONKEY_ENGINE = []" >> .emscripten
echo "BINARYEN_ROOT = '${binaryen}'" >> .emscripten
# make emconfigure/emcmake use the correct (wrapped) binaries
sed -i "s|^EMCC =.*|EMCC='$out/bin/emcc'|" tools/shared.py
sed -i "s|^EMXX =.*|EMXX='$out/bin/em++'|" tools/shared.py
sed -i "s|^EMAR =.*|EMAR='$out/bin/emar'|" tools/shared.py
sed -i "s|^EMRANLIB =.*|EMRANLIB='$out/bin/emranlib'|" tools/shared.py
# Fix /tmp symlink issue (macOS: /tmp -> /private/tmp) causing relpath miscalculation
sed -i 's/os\.path\.relpath(source_dir, build_dir)/os.path.relpath(source_dir, os.path.realpath(build_dir))/' tools/system_libs.py
sed -i 's/os\.path\.relpath(src, build_dir)/os.path.relpath(src, os.path.realpath(build_dir))/' tools/system_libs.py
# Verify the relpath fix was applied
grep -q 'os.path.realpath(build_dir)' tools/system_libs.py || (echo "ERROR: relpath fix not applied" && exit 1)
# Functional test: verify relpath resolves correctly through symlinks
${python3}/bin/python3 -c "
import os, tempfile
src = os.path.abspath('tools/system_libs.py')
with tempfile.TemporaryDirectory() as tmpdir:
build_dir_real = os.path.realpath(tmpdir)
relpath = os.path.relpath(src, build_dir_real)
resolved = os.path.normpath(os.path.join(build_dir_real, relpath))
assert resolved == src, f'relpath test failed: {resolved} != {src}'
print('relpath symlink fix test passed')
"
runHook postBuild
'';
installPhase = ''
runHook preInstall
appdir=$out/share/emscripten
mkdir -p $appdir
cp -r . $appdir
chmod -R +w $appdir
mkdir -p $appdir/node_modules/.bin
cp -r ${nodeModules}/* $appdir/node_modules
cp -r ${nodeModules}/* $appdir/node_modules/.bin
cp ${./locate_cache.sh} $appdir/locate_cache.sh
chmod +x $appdir/locate_cache.sh
export EM_CACHE=$out/share/emscripten/cache
mkdir -p $out/bin
# Wrap all tools consistently via their .py entry points
for b in em++ emcc em-config emar embuilder emcmake emconfigure emmake emranlib emrun emscons emsize; do
makeWrapper $appdir/$b.py $out/bin/$b \
--set NODE_PATH ${nodeModules} \
--set EM_EXCLUSIVE_CACHE_ACCESS 1 \
--set PYTHON ${python3}/bin/python \
--run "source $appdir/locate_cache.sh"
done
# Create extensionless aliases for tools that need them (e.g., file_packager)
for tool in file_packager; do
ln -sf $appdir/tools/$tool.py $appdir/tools/$tool
done
# Symlinks for CMake toolchain (expects tools in share/emscripten/)
for tool in emcc em++ em-config emar emranlib emcmake emconfigure; do
ln -sf $out/bin/$tool $appdir/$tool
done
# precompile libc (etc.) in all variants:
pushd $TMPDIR
echo 'int __main_argc_argv( int a, int b ) { return 42; }' >test.c
for LTO in -flto ""; do
for BIND in "" "--bind"; do
for PTHREAD in "" "-pthread"; do
$out/bin/emcc $LTO $BIND $PTHREAD test.c || true
done
done
done
popd
export PYTHON=${python3}/bin/python
export NODE_PATH=${nodeModules}
pushd $appdir
${pythonWithPsutil}/bin/python test/runner.py test_hello_world
popd
# fail if any .py files still have unpatched shebangs
if grep -l '#!/usr/bin/env' $appdir/*.py $appdir/tools/*.py 2>/dev/null; then
echo "ERROR: unpatched shebangs found in .py files"
exit 1
fi
runHook postInstall
'';
doInstallCheck = true;
# C++ exceptions with -fwasm-exceptions must compile and link
# see https://github.com/NixOS/nixpkgs/pull/556385
installCheckPhase = ''
runHook preInstallCheck
pushd $TMPDIR
echo 'int main() { try { throw 42; } catch (int) { return 0; } return 1; }' > throw.cpp
$out/bin/em++ -fwasm-exceptions throw.cpp -o throw.js
popd
runHook postInstallCheck
'';
passthru = {
# HACK: Make emscripten look more like a cc-wrapper to GHC
# when building the javascript backend.
targetPrefix = "em";
bintools = emscripten;
updateScript = nix-update-script {
extraArgs = [
"--subpackage"
"nodeModules"
];
};
};
meta = {
homepage = "https://github.com/emscripten-core/emscripten";
description = "LLVM-to-JavaScript Compiler";
platforms = lib.platforms.all;
maintainers = with lib.maintainers; [
qknight
willcohen
];
license = lib.licenses.ncsa;
};
}
|
