From c814c858dc97fec6908bf573b79fc0eaf4b1dbf1 Mon Sep 17 00:00:00 2001 From: Deepesh Varatharajan Date: Fri, 26 Sep 2025 03:24:06 -0700 Subject: [PATCH] rust: Use clang instead of rust-llvm Updated the Rust build to depend on Clang instead. *Summary of discussion with the rust upstream about using latest LLVM instead of Rust maintained LLVM fork. https://internals.rust-lang.org/t/can-we-use-proper-clang-instead-of-llvm-fork-what-rust-uses/23489 *Upstream LLVM is generally compatible: - Rust does support building with upstream (vanilla) LLVM, especially the latest major release and the one or two preceding ones. https://rustc-dev-guide.rust-lang.org/backend/updating-llvm.html#updating-llvm *Impact on Yocto Rust upgrades: - Rust upgrades shall always check for updates on rust forked llvm and backport the relevant patches to clang's llvm. *Regarding the rust forked llvm local patches: - There are no local patches on rust forked llvm other than the backported fixes from llvm master. *We now add these flags "-Clink-arg=-lz -Clink-arg=-lzstd" because of this following diff otherwise we will get errors during link time. Setup in rust-llvm -DLLVM_ENABLE_ZLIB=OFF \ -DLLVM_ENABLE_ZSTD=OFF \ -DLLVM_ENABLE_FFI=OFF \ Setup in clang -DLLVM_ENABLE_FFI=ON \ -DLLVM_ENABLE_ZSTD=ON \ *When multilibs enabled: llvm-config expects static libraries to be located in the lib directory rather than lib64. However, since LLVM is built as a non-multilib component, the lib directory doesn't contain any library files. To accommodate this without breaking multilib behavior, we copy the required library files appropriately. Previously, when we depended on rust-llvm, this worked because we specified: -DCMAKE_INSTALL_PREFIX:PATH=${libdir}/llvm-rust With this setup, llvm-config was installed inside ${libdir}/llvm-rust, which included its own bin and lib directories. Thus, llvm-config located in bin would correctly find the libraries in the adjacent lib directory. Even when multilib was enabled or not, llvm-config would still look for libraries under lib in this structure, so everything functioned as expected. *Changes needs to be done when llvm splits from clang: In rust recipe: Update the dependency from: DEPENDS += "ninja-native clang" to DEPENDS += "ninja-native llvm" In llvm recipe: Apply the same changes that were made in the Clang recipe, as those configurations have now been moved to the LLVM recipe after the split. Signed-off-by: Deepesh Varatharajan Signed-off-by: Mathieu Dubois-Briand --- meta/recipes-devtools/clang/clang_git.bb | 4 ++-- meta/recipes-devtools/clang/common-clang.inc | 6 +++--- meta/recipes-devtools/rust/rust_1.90.0.bb | 18 ++++++++++++++---- 3 files changed, 19 insertions(+), 9 deletions(-) diff --git a/meta/recipes-devtools/clang/clang_git.bb b/meta/recipes-devtools/clang/clang_git.bb index 53bca1c24f..3e117b308b 100644 --- a/meta/recipes-devtools/clang/clang_git.bb +++ b/meta/recipes-devtools/clang/clang_git.bb @@ -83,7 +83,6 @@ OECMAKE_SOURCEPATH = "${S}/llvm" # https://github.com/llvm/llvm-project/blob/main/llvm/CMakeLists.txt LLVM_TARGETS_GPU ?= "${@bb.utils.contains_any('DISTRO_FEATURES', 'opencl opengl vulkan', 'AMDGPU;NVPTX;SPIRV', '', d)}" LLVM_TARGETS_TO_BUILD ?= "AArch64;ARM;BPF;Mips;PowerPC;RISCV;X86;LoongArch;${LLVM_TARGETS_GPU}" -LLVM_TARGETS_TO_BUILD:class-target ?= "${@get_clang_host_arch(bb, d)};BPF;${LLVM_TARGETS_GPU}" LLVM_EXPERIMENTAL_TARGETS_TO_BUILD ?= "" @@ -107,6 +106,7 @@ EXTRA_OECMAKE += "-DLLVM_ENABLE_ASSERTIONS=OFF \ -DLLVM_ENABLE_PIC=ON \ -DCLANG_DEFAULT_PIE_ON_LINUX=ON \ -DLLVM_BINDINGS_LIST='' \ + -DLLVM_INSTALL_UTILS=ON \ -DLLVM_ENABLE_FFI=ON \ -DLLVM_ENABLE_ZSTD=ON \ -DFFI_INCLUDE_DIR=$(pkg-config --variable=includedir libffi) \ @@ -137,7 +137,7 @@ EXTRA_OECMAKE:append:class-target = "\ -DCMAKE_AR=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}llvm-ar \ -DCMAKE_NM=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}llvm-nm \ -DCMAKE_STRIP=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}llvm-strip \ - -DLLVM_TARGET_ARCH=${HOST_ARCH} \ + -DLLVM_TARGET_ARCH=${@get_clang_target_arch(bb, d)} \ -DLLVM_DEFAULT_TARGET_TRIPLE=${TARGET_SYS}${HF} \ -DLLVM_HOST_TRIPLE=${TARGET_SYS}${HF} \ -DLLVM_LIBDIR_SUFFIX=${LLVM_LIBDIR_SUFFIX} \ diff --git a/meta/recipes-devtools/clang/common-clang.inc b/meta/recipes-devtools/clang/common-clang.inc index bf3a63914a..c22e3c1b19 100644 --- a/meta/recipes-devtools/clang/common-clang.inc +++ b/meta/recipes-devtools/clang/common-clang.inc @@ -30,10 +30,10 @@ def get_clang_arch(bb, d, arch_var): elif re.match('aarch64$', a): return 'AArch64' elif re.match('aarch64_be$', a): return 'AArch64' elif re.match('mips(isa|)(32|64|)(r6|)(el|)$', a): return 'Mips' - elif re.match('riscv32$', a): return 'RISCV' - elif re.match('riscv64$', a): return 'RISCV' + elif re.match('riscv32$', a): return 'riscv32' + elif re.match('riscv64$', a): return 'riscv64' elif re.match('p(pc|owerpc)(|64)', a): return 'PowerPC' - elif re.match('loongarch64$', a): return 'LoongArch' + elif re.match('loongarch64$', a): return 'loongarch64' else: bb.fatal("Unhandled architecture %s" % arch_val) return "" diff --git a/meta/recipes-devtools/rust/rust_1.90.0.bb b/meta/recipes-devtools/rust/rust_1.90.0.bb index 5d804c7398..c2cb8f8829 100644 --- a/meta/recipes-devtools/rust/rust_1.90.0.bb +++ b/meta/recipes-devtools/rust/rust_1.90.0.bb @@ -7,7 +7,7 @@ LIC_FILES_CHKSUM = "file://COPYRIGHT;md5=11a3899825f4376896e438c8c753f8dc" inherit rust inherit cargo_common -DEPENDS += "rust-llvm" +DEPENDS += "ninja-native clang" # native rust uses cargo/rustc from binary snapshots to bootstrap # but everything else should use our native builds DEPENDS:append:class-target = " cargo-native rust-native" @@ -28,8 +28,8 @@ PV .= "${@bb.utils.contains('RUST_CHANNEL', 'stable', '', '-${RUST_CHANNEL}', d) export FORCE_CRATE_HASH = "${BB_TASKHASH}" -RUST_ALTERNATE_EXE_PATH ?= "${STAGING_LIBDIR}/llvm-rust/bin/llvm-config" -RUST_ALTERNATE_EXE_PATH_NATIVE = "${STAGING_LIBDIR_NATIVE}/llvm-rust/bin/llvm-config" +RUST_ALTERNATE_EXE_PATH ?= "${STAGING_BINDIR}/llvm-config" +RUST_ALTERNATE_EXE_PATH_NATIVE = "${STAGING_BINDIR_NATIVE}/llvm-config" # We don't want to use bitbakes vendoring because the rust sources do their # own vendoring. @@ -188,6 +188,16 @@ python do_configure() { bb.build.exec_func("setup_cargo_environment", d) } +#llvm-config expecting static libraries in 'lib' instead of 'lib64'. +#Since LLVM is built as a non-multilib component, the 'lib' directory +#doesn't have any library files when multilibs enabled. So, copying +#library files without impacting multilib behavior. +do_compile:append:class-target() { +if [ -d ${STAGING_DIR_TARGET}/usr/lib64 ]; then + cp ${STAGING_DIR_TARGET}/usr/lib64/libLLVM*.a ${STAGING_DIR_TARGET}/usr/lib/. +fi +} + rust_runx () { echo "COMPILE ${PN}" "$@" @@ -199,7 +209,7 @@ rust_runx () { unset CXXFLAGS unset CPPFLAGS - export RUSTFLAGS="${RUST_DEBUG_REMAP}" + export RUSTFLAGS="${RUST_DEBUG_REMAP} -Clink-arg=-lz -Clink-arg=-lzstd" # Copy the natively built llvm-config into the target so we can run it. Horrible, # but works! -- 2.47.3