core-agent-ide/.github/scripts/install-musl-build-tools.sh
Michael Bolin 08a000866f
Fix linux-musl release link failures caused by glibc-only libcap artifacts (#11556)
Problem:
The `aarch64-unknown-linux-musl` release build was failing at link time
with
`/usr/bin/ld: cannot find -lcap` while building binaries that
transitively pull
in `codex-linux-sandbox`.

Why this is the right fix:
`codex-linux-sandbox` compiles vendored bubblewrap and links `libcap`.
In the
musl jobs, we were installing distro `libcap-dev`, which provides
host/glibc
artifacts. That is not a valid source of target-compatible static libcap
for
musl cross-linking, so the fix is to produce a target-compatible libcap
inside
the musl tool bootstrap and point pkg-config at it.

This also closes the CI coverage gap that allowed this to slip through:
the
`rust-ci.yml` matrix did not exercise `aarch64-unknown-linux-musl` in
`release`
mode. Adding that target/profile combination to CI is the right
regression
barrier for this class of failure.

What changed:
- Updated `.github/scripts/install-musl-build-tools.sh` to install
tooling
  needed to fetch/build libcap sources (`curl`, `xz-utils`, certs).
- Added deterministic libcap bootstrap in the musl tool root:
  - download `libcap-2.75` from kernel.org
  - verify SHA256
  - build with the target musl compiler (`*-linux-musl-gcc`)
  - stage `libcap.a` and headers under the target tool root
  - generate a target-scoped `libcap.pc`
- Exported target `PKG_CONFIG_PATH` so builds resolve the staged musl
libcap
  instead of host pkg-config/lib paths.
- Updated `.github/workflows/rust-ci.yml` to add a `release` matrix
entry for
  `aarch64-unknown-linux-musl` on the ARM runner.
- Updated `.github/workflows/rust-ci.yml` to set
`CARGO_PROFILE_RELEASE_LTO=thin` for `release` matrix entries (and keep
`fat`
for non-release entries), matching the release-build tradeoff already
used in
  `rust-release.yml` while reducing CI runtime.

Verification:
- Reproduced the original failure in CI-like containers:
  - `aarch64-unknown-linux-musl` failed with `cannot find -lcap`.
- Verified the underlying mismatch by forcing host libcap into the link:
  - link then failed with glibc-specific unresolved symbols
    (`__isoc23_*`, `__*_chk`), confirming host libcap was unsuitable.
- Verified the fix in CI-like containers after this change:
- `cargo build -p codex-linux-sandbox --target
aarch64-unknown-linux-musl --release` -> pass
- `cargo build -p codex-linux-sandbox --target x86_64-unknown-linux-musl
--release` -> pass
- Triggered `rust-ci` on this branch and confirmed the new job appears:
- `Lint/Build — ubuntu-24.04-arm - aarch64-unknown-linux-musl (release)`
2026-02-12 08:08:32 +00:00

279 lines
8.3 KiB
Bash

#!/usr/bin/env bash
set -euo pipefail
: "${TARGET:?TARGET environment variable is required}"
: "${GITHUB_ENV:?GITHUB_ENV environment variable is required}"
apt_update_args=()
if [[ -n "${APT_UPDATE_ARGS:-}" ]]; then
# shellcheck disable=SC2206
apt_update_args=(${APT_UPDATE_ARGS})
fi
apt_install_args=()
if [[ -n "${APT_INSTALL_ARGS:-}" ]]; then
# shellcheck disable=SC2206
apt_install_args=(${APT_INSTALL_ARGS})
fi
sudo apt-get update "${apt_update_args[@]}"
sudo apt-get install -y "${apt_install_args[@]}" ca-certificates curl musl-tools pkg-config libcap-dev g++ clang libc++-dev libc++abi-dev lld xz-utils
case "${TARGET}" in
x86_64-unknown-linux-musl)
arch="x86_64"
;;
aarch64-unknown-linux-musl)
arch="aarch64"
;;
*)
echo "Unexpected musl target: ${TARGET}" >&2
exit 1
;;
esac
libcap_version="2.75"
libcap_sha256="de4e7e064c9ba451d5234dd46e897d7c71c96a9ebf9a0c445bc04f4742d83632"
libcap_tarball_name="libcap-${libcap_version}.tar.xz"
libcap_download_url="https://mirrors.edge.kernel.org/pub/linux/libs/security/linux-privs/libcap2/${libcap_tarball_name}"
# Use the musl toolchain as the Rust linker to avoid Zig injecting its own CRT.
if command -v "${arch}-linux-musl-gcc" >/dev/null; then
musl_linker="$(command -v "${arch}-linux-musl-gcc")"
elif command -v musl-gcc >/dev/null; then
musl_linker="$(command -v musl-gcc)"
else
echo "musl gcc not found after install; arch=${arch}" >&2
exit 1
fi
zig_target="${TARGET/-unknown-linux-musl/-linux-musl}"
runner_temp="${RUNNER_TEMP:-/tmp}"
tool_root="${runner_temp}/codex-musl-tools-${TARGET}"
mkdir -p "${tool_root}"
libcap_root="${tool_root}/libcap-${libcap_version}"
libcap_src_root="${libcap_root}/src"
libcap_prefix="${libcap_root}/prefix"
libcap_pkgconfig_dir="${libcap_prefix}/lib/pkgconfig"
if [[ ! -f "${libcap_prefix}/lib/libcap.a" ]]; then
mkdir -p "${libcap_src_root}" "${libcap_prefix}/lib" "${libcap_prefix}/include/sys" "${libcap_prefix}/include/linux" "${libcap_pkgconfig_dir}"
libcap_tarball="${libcap_root}/${libcap_tarball_name}"
curl -fsSL "${libcap_download_url}" -o "${libcap_tarball}"
echo "${libcap_sha256} ${libcap_tarball}" | sha256sum -c -
tar -xJf "${libcap_tarball}" -C "${libcap_src_root}"
libcap_source_dir="${libcap_src_root}/libcap-${libcap_version}"
make -C "${libcap_source_dir}/libcap" -j"$(nproc)" \
CC="${musl_linker}" \
AR=ar \
RANLIB=ranlib
cp "${libcap_source_dir}/libcap/libcap.a" "${libcap_prefix}/lib/libcap.a"
cp "${libcap_source_dir}/libcap/include/uapi/linux/capability.h" "${libcap_prefix}/include/linux/capability.h"
cp "${libcap_source_dir}/libcap/../libcap/include/sys/capability.h" "${libcap_prefix}/include/sys/capability.h"
cat > "${libcap_pkgconfig_dir}/libcap.pc" <<EOF
prefix=${libcap_prefix}
exec_prefix=\${prefix}
libdir=\${prefix}/lib
includedir=\${prefix}/include
Name: libcap
Description: Linux capabilities
Version: ${libcap_version}
Libs: -L\${libdir} -lcap
Cflags: -I\${includedir}
EOF
fi
sysroot=""
if command -v zig >/dev/null; then
zig_bin="$(command -v zig)"
cc="${tool_root}/zigcc"
cxx="${tool_root}/zigcxx"
cat >"${cc}" <<EOF
#!/usr/bin/env bash
set -euo pipefail
args=()
skip_next=0
pending_include=0
for arg in "\$@"; do
if [[ "\${pending_include}" -eq 1 ]]; then
pending_include=0
if [[ "\${arg}" == /usr/include || "\${arg}" == /usr/include/* ]]; then
# Keep host-only headers available, but after the target sysroot headers.
args+=("-idirafter" "\${arg}")
else
args+=("-I" "\${arg}")
fi
continue
fi
if [[ "\${skip_next}" -eq 1 ]]; then
skip_next=0
continue
fi
case "\${arg}" in
--target)
skip_next=1
continue
;;
--target=*|-target=*|-target)
# Drop any explicit --target/-target flags. Zig expects -target and
# rejects Rust triples like *-unknown-linux-musl.
if [[ "\${arg}" == "-target" ]]; then
skip_next=1
fi
continue
;;
-I)
pending_include=1
continue
;;
-I/usr/include|-I/usr/include/*)
# Avoid making glibc headers win over musl headers.
args+=("-idirafter" "\${arg#-I}")
continue
;;
-Wp,-U_FORTIFY_SOURCE)
# aws-lc-sys emits this GCC preprocessor forwarding form in debug
# builds, but zig cc expects the define flag directly.
args+=("-U_FORTIFY_SOURCE")
continue
;;
esac
args+=("\${arg}")
done
exec "${zig_bin}" cc -target "${zig_target}" "\${args[@]}"
EOF
cat >"${cxx}" <<EOF
#!/usr/bin/env bash
set -euo pipefail
args=()
skip_next=0
pending_include=0
for arg in "\$@"; do
if [[ "\${pending_include}" -eq 1 ]]; then
pending_include=0
if [[ "\${arg}" == /usr/include || "\${arg}" == /usr/include/* ]]; then
# Keep host-only headers available, but after the target sysroot headers.
args+=("-idirafter" "\${arg}")
else
args+=("-I" "\${arg}")
fi
continue
fi
if [[ "\${skip_next}" -eq 1 ]]; then
skip_next=0
continue
fi
case "\${arg}" in
--target)
# Drop explicit --target and its value: we always pass zig's -target below.
skip_next=1
continue
;;
--target=*|-target=*|-target)
# Zig expects -target and rejects Rust triples like *-unknown-linux-musl.
if [[ "\${arg}" == "-target" ]]; then
skip_next=1
fi
continue
;;
-I)
pending_include=1
continue
;;
-I/usr/include|-I/usr/include/*)
# Avoid making glibc headers win over musl headers.
args+=("-idirafter" "\${arg#-I}")
continue
;;
-Wp,-U_FORTIFY_SOURCE)
# aws-lc-sys emits this GCC forwarding form in debug builds; zig c++
# expects the define flag directly.
args+=("-U_FORTIFY_SOURCE")
continue
;;
esac
args+=("\${arg}")
done
exec "${zig_bin}" c++ -target "${zig_target}" "\${args[@]}"
EOF
chmod +x "${cc}" "${cxx}"
sysroot="$("${zig_bin}" cc -target "${zig_target}" -print-sysroot 2>/dev/null || true)"
else
cc="${musl_linker}"
if command -v "${arch}-linux-musl-g++" >/dev/null; then
cxx="$(command -v "${arch}-linux-musl-g++")"
elif command -v musl-g++ >/dev/null; then
cxx="$(command -v musl-g++)"
else
cxx="${cc}"
fi
fi
if [[ -n "${sysroot}" && "${sysroot}" != "/" ]]; then
echo "BORING_BSSL_SYSROOT=${sysroot}" >> "$GITHUB_ENV"
boring_sysroot_var="BORING_BSSL_SYSROOT_${TARGET}"
boring_sysroot_var="${boring_sysroot_var//-/_}"
echo "${boring_sysroot_var}=${sysroot}" >> "$GITHUB_ENV"
fi
cflags="-pthread"
cxxflags="-pthread"
if [[ "${TARGET}" == "aarch64-unknown-linux-musl" ]]; then
# BoringSSL enables -Wframe-larger-than=25344 under clang and treats warnings as errors.
cflags="${cflags} -Wno-error=frame-larger-than"
cxxflags="${cxxflags} -Wno-error=frame-larger-than"
fi
echo "CFLAGS=${cflags}" >> "$GITHUB_ENV"
echo "CXXFLAGS=${cxxflags}" >> "$GITHUB_ENV"
echo "CC=${cc}" >> "$GITHUB_ENV"
echo "TARGET_CC=${cc}" >> "$GITHUB_ENV"
target_cc_var="CC_${TARGET}"
target_cc_var="${target_cc_var//-/_}"
echo "${target_cc_var}=${cc}" >> "$GITHUB_ENV"
echo "CXX=${cxx}" >> "$GITHUB_ENV"
echo "TARGET_CXX=${cxx}" >> "$GITHUB_ENV"
target_cxx_var="CXX_${TARGET}"
target_cxx_var="${target_cxx_var//-/_}"
echo "${target_cxx_var}=${cxx}" >> "$GITHUB_ENV"
cargo_linker_var="CARGO_TARGET_${TARGET^^}_LINKER"
cargo_linker_var="${cargo_linker_var//-/_}"
echo "${cargo_linker_var}=${musl_linker}" >> "$GITHUB_ENV"
echo "CMAKE_C_COMPILER=${cc}" >> "$GITHUB_ENV"
echo "CMAKE_CXX_COMPILER=${cxx}" >> "$GITHUB_ENV"
echo "CMAKE_ARGS=-DCMAKE_HAVE_THREADS_LIBRARY=1 -DCMAKE_USE_PTHREADS_INIT=1 -DCMAKE_THREAD_LIBS_INIT=-pthread -DTHREADS_PREFER_PTHREAD_FLAG=ON" >> "$GITHUB_ENV"
# Allow pkg-config resolution during cross-compilation.
echo "PKG_CONFIG_ALLOW_CROSS=1" >> "$GITHUB_ENV"
pkg_config_path="${libcap_pkgconfig_dir}"
if [[ -n "${PKG_CONFIG_PATH:-}" ]]; then
pkg_config_path="${pkg_config_path}:${PKG_CONFIG_PATH}"
fi
echo "PKG_CONFIG_PATH=${pkg_config_path}" >> "$GITHUB_ENV"
pkg_config_path_var="PKG_CONFIG_PATH_${TARGET}"
pkg_config_path_var="${pkg_config_path_var//-/_}"
echo "${pkg_config_path_var}=${libcap_pkgconfig_dir}" >> "$GITHUB_ENV"
if [[ -n "${sysroot}" && "${sysroot}" != "/" ]]; then
echo "PKG_CONFIG_SYSROOT_DIR=${sysroot}" >> "$GITHUB_ENV"
pkg_config_sysroot_var="PKG_CONFIG_SYSROOT_DIR_${TARGET}"
pkg_config_sysroot_var="${pkg_config_sysroot_var//-/_}"
echo "${pkg_config_sysroot_var}=${sysroot}" >> "$GITHUB_ENV"
fi