llvm-native: re-architect as a PURE HOST build (fixes libclc host-LLVM)

llvm-native's job is to supply a COMPLETE host LLVM dev tree (host clang + host static component libs + matching cmake/llvm export) that libclc's find_package(LLVM) and host clang need for Mesa's iris/radeonsi CLC path. The redoxer toolchain ships host clang + libLLVM.so but strips the static libs, so find_package fails — and stubbing them violates the no-stub policy. The recipe was WRONGLY cross-compiling LLVM for the Redox target via cookbook_cmake: that (a) produces host-unusable Redox binaries and (b) fails to link because Redox's libstdc++ lacks symbols LLVM uses (std::random_device etc.). My earlier LLVM_USE_HOST_TOOLS=OFF / tblgen-var / native.cmake patches were all treating symptoms of that wrong architecture. Rewrite: build entirely with the host gcc, targeting the host, exactly like libclc builds its own host prepare_builtins tool — invoke cmake directly (not cookbook_cmake) with /usr/bin/gcc and no CMAKE_SYSTEM_NAME so CROSSCOMPILING is false (LLVM builds one native tblgen with host gcc; no NATIVE sub-project, no Redox-header leak). Drop all Redox build-deps and the llvm21.runtime package dep. Validated: host GCC 16.1.1 configures LLVM 21 and builds llvm-min-tblgen + libLLVMSupport.a/libLLVMTableGen.a cleanly. This is how upstream-style host LLVM tooling should be produced; it supersedes the cross-build patch chain (312659fe21, 5d426d89a7, 872935057c, b2d9a31a4f).
2026-07-31 08:18:46 +03:00
parent b2d9a31a4f
commit ecc971b4ec
1 changed files with 69 additions and 143 deletions
@@ -3,158 +3,84 @@ same_as = "../../../../recipes/dev/llvm21"

 [build]
 template = "custom"
-dependencies = [
-    "llvm21",
-    "llvm21.runtime",
-    "llvm21.dev",
-    "clang21",
-    "lld21",
-    "zstd",
-]
+# PURE HOST build — needs nothing from the Redox cross sysroot. (It shares the
+# llvm21 SOURCE via [source] same_as, which is a source relationship, not a
+# build dependency.)
+dependencies = []
 script = """
 DYNAMIC_INIT
 ARCH="$(echo "${TARGET}" | cut -d - -f1)"
-
-# Save and unset the cross-compile flags DYNAMIC_INIT exports so the host cc
-# in the native sub-build (CROSS_TOOLCHAIN_FLAGS_NATIVE below) links against
-# the host libc, not the Redox sysroot's relibc — otherwise the native cmake
-# try_compile fails with "undefined reference to __libc_start_main". The cross
-# build restores them via -DCMAKE_*_FLAGS further down. Mirrors the llvm21
-# recipe, which solved this exact failure.
-_SAVED_LDFLAGS="${LDFLAGS:-}"
-_SAVED_CFLAGS="${CFLAGS:-}"
-_SAVED_CXXFLAGS="${CXXFLAGS:-}"
-unset LDFLAGS CFLAGS CXXFLAGS
-
-# Use /usr (host sysroot) for the native build, NOT $COOKBOOK_TOOLCHAIN (the
-# Redox cross sysroot whose libc.a lacks __libc_start_main).
-generate_cookbook_cmake_file "$COOKBOOK_HOST_TARGET" "" "/usr" native.cmake
-
-# The generated native.cmake still inherits CMAKE_*_FLAGS / sysroot from the
-# cross toolchain via the cache; CACHE FORCE is required because try_compile
-# creates a sub-cache that re-reads the parent values unless explicitly forced.
-cat >> native.cmake <<'NATIVE_EOF'
-
-# Override cross-sysroot flags so the host cc links against the host libc.
-set(CMAKE_C_FLAGS "" CACHE STRING "" FORCE)
-set(CMAKE_CXX_FLAGS "" CACHE STRING "" FORCE)
-set(CMAKE_CXX_FLAGS_DEBUG "" CACHE STRING "" FORCE)
-set(CMAKE_CXX_FLAGS_RELEASE "" CACHE STRING "" FORCE)
-set(CMAKE_C_FLAGS_DEBUG "" CACHE STRING "" FORCE)
-set(CMAKE_C_FLAGS_RELEASE "" CACHE STRING "" FORCE)
-set(CMAKE_LDFLAGS "" CACHE STRING "" FORCE)
-set(CMAKE_LDFLAGS_DEBUG "" CACHE STRING "" FORCE)
-set(CMAKE_LDFLAGS_RELEASE "" CACHE STRING "" FORCE)
-set(CMAKE_EXE_LINKER_FLAGS "" CACHE STRING "" FORCE)
-set(CMAKE_SHARED_LINKER_FLAGS "" CACHE STRING "" FORCE)
-set(CMAKE_C_IMPLICIT_LINK_DIRECTORIES "" CACHE STRING "" FORCE)
-set(CMAKE_CXX_IMPLICIT_LINK_DIRECTORIES "" CACHE STRING "" FORCE)
-set(CMAKE_SYSROOT "" CACHE STRING "" FORCE)
-set(CMAKE_FIND_ROOT_PATH "" CACHE STRING "" FORCE)
-set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM "NEVER" CACHE STRING "" FORCE)
-set(ENV{LDFLAGS} "")
-set(ENV{CFLAGS} "")
-set(ENV{CXXFLAGS} "")
-NATIVE_EOF
-
 case "${ARCH}" in
-    x86 | x86_64) LLVM_TARGETS_TO_BUILD="X86";;
-    aarch64) LLVM_TARGETS_TO_BUILD="AArch64";;
-    riscv64gc) LLVM_TARGETS_TO_BUILD="RISCV";;
+    x86 | x86_64) LLVM_HOST_ARCH="X86";;
+    aarch64) LLVM_HOST_ARCH="AArch64";;
+    riscv64gc) LLVM_HOST_ARCH="RISCV";;
 esac

-# The *-tblgen references below must be VERSION-MATCHED to this LLVM source
-# tree. cookbook does not export COOKBOOK_HOST_SYSROOT, so an unset value
-# collapses them to "/bin/{llvm,clang}-tblgen" — the rolling distro LLVM (now
-# 22), whose -gen-opt-parser-defs backend requires a `SubCommand` class that
-# LLVM 21's OptParser.td does not define. Point at the redoxer toolchain's
-# host-runnable LLVM 21.1.2 tblgen, matching the clang21/lld21 recipes.
-export COOKBOOK_HOST_SYSROOT="${COOKBOOK_HOST_SYSROOT:-${HOME}/.redoxer/${TARGET}/toolchain}"
+# ============================================================================
+# llvm-native is a PURE HOST build of LLVM/Clang/LLD 21.
+#
+# Its whole purpose is to supply a COMPLETE host LLVM dev tree (host-runnable
+# clang + host static component libs + a matching cmake/llvm export) that
+# libclc's `find_package(LLVM)` and host `clang` need to compile the OpenCL-C
+# builtins bitcode Mesa's iris/radeonsi CLC path consumes. The redoxer
+# toolchain ships a host clang + libLLVM.so but STRIPS the static component
+# libs, so its LLVMExports references files that don't exist and find_package
+# fails — and faking them with stub archives violates the no-stub policy.
+#
+# It must NOT be cross-compiled for Redox (the previous mistake): a
+# Redox-target LLVM (a) produces binaries that can't run on the build host and
+# (b) fails to LINK because Redox's libstdc++ lacks symbols LLVM uses
+# (e.g. std::random_device). So we build entirely with the HOST gcc, targeting
+# the host, exactly the way libclc builds its own host prepare_builtins tool.
+#
+# We deliberately do NOT use cookbook_cmake (which configures a Redox
+# cross-build). We invoke cmake directly with the host gcc and no
+# CMAKE_SYSTEM_NAME, so CMAKE_CROSSCOMPILING is false: LLVM builds its own
+# native tblgen once (host gcc → no Redox-header leak) and there is no NATIVE
+# external sub-project.
+# ============================================================================

-COOKBOOK_CMAKE_FLAGS+=(
-    -DLLVM_ENABLE_PROJECTS="clang;lld"
-    -DLLVM_BUILD_LLVM_DYLIB=On
-    -DLLVM_LINK_LLVM_DYLIB=On
-    -DLLVM_INCLUDE_UTILS=On
-    -DLLVM_INSTALL_UTILS=On
-    -DLLVM_TARGETS_TO_BUILD="$LLVM_TARGETS_TO_BUILD"
-    -DLLVM_ENABLE_ZLIB=Off
-    -DLLVM_USE_STATIC_ZSTD=On
-    -DLLVM_ENABLE_LIBXML2=Off
-    -DCLANG_LINK_CLANG_DYLIB=ON
-    -DLIBCLANG_BUILD_STATIC=1
-    -DCROSS_TOOLCHAIN_FLAGS_NATIVE="-DCMAKE_TOOLCHAIN_FILE=$(realpath native.cmake)"
-    -DBUILD_SHARED_LIBS=False
-    -DLLVM_BUILD_EXAMPLES=Off
-    -DLLVM_BUILD_TESTS=Off
-    -DLLVM_DEFAULT_TARGET_TRIPLE="${TARGET}"
-    -DLLVM_ENABLE_LTO=Off
-    -DLLVM_ENABLE_RTTI=On
-    -DLLVM_ENABLE_THREADS=On
-    -DLLVM_INCLUDE_EXAMPLES=Off
-    -DLLVM_INCLUDE_TESTS=Off
-    # OFF on purpose: this recipe PROVIDES host-runnable, version-matched
-    # tblgens via LLVM_TABLEGEN/CLANG_TABLEGEN below (the redoxer toolchain's
-    # LLVM 21.1.2). LLVM_OPTIMIZED_TABLEGEN=On would build a second optimized
-    # native tblgen instead of using them. Off => LLVM uses what we provide.
-    -DLLVM_OPTIMIZED_TABLEGEN=Off
-    # OFF is REQUIRED here. LLVM_USE_HOST_TOOLS defaults ON when cross-compiling
-    # and makes llvm/CMakeLists.txt create the NATIVE external project
-    # (llvm_create_cross_target LLVM NATIVE), a full second host LLVM build that
-    # inherits the Redox cross flags and dies compiling native llvm-config/etc.
-    # We already supply host-runnable, version-matched tblgens via
-    # LLVM_TABLEGEN/CLANG_TABLEGEN (the only native tools a cross-build needs),
-    # so the NATIVE project is pure waste. OFF => no native sub-build; LLVM uses
-    # the provided tblgens for .inc generation.
-    -DLLVM_USE_HOST_TOOLS=OFF
-    -DLLVM_TARGET_ARCH=$ARCH
-    -DLLVM_TOOLS_INSTALL_DIR=bin
-    -DLLVM_UTILS_INSTALL_DIR=bin
-    -DUNIX=1
-    # CRITICAL: the cache vars LLVM/Clang read to SKIP building a native tblgen
-    # when cross-compiling are LLVM_TABLEGEN / CLANG_TABLEGEN (see
-    # llvm/cmake/modules/TableGen.cmake: "Native TableGen executable. Saves
-    # building one when cross-compiling"). The *_TABLEGEN_EXE names used
-    # previously are NOT read by a from-scratch LLVM build, so LLVM built its
-    # own native tblgen via the CROSS_TOOLCHAIN_FLAGS_NATIVE sub-build — which
-    # ran the HOST gcc against the Redox relibc headers leaked through
-    # CMAKE_CXX_FLAGS and died on host/redox <stdlib.h> conflicts
-    # (__deprecated/__noreturn undeclared, duplicate div_t). Passing the
-    # correct var names makes LLVM use the provided host tblgens (LLVM 21.1.2)
-    # and skip the native sub-build entirely. (lld21/clang21 build against a
-    # PREBUILT llvm and locate tblgen via find_program on LLVM_TABLEGEN_EXE —
-    # a different cache var owned by those projects — so they are correct.)
-    -DLLVM_TABLEGEN=${COOKBOOK_HOST_SYSROOT}/bin/llvm-tblgen
-    -DCLANG_TABLEGEN=${COOKBOOK_HOST_SYSROOT}/bin/clang-tblgen
-)
+# Drop every cross-compile flag DYNAMIC_INIT exported so the host gcc never
+# sees the Redox sysroot / relibc.
+unset LDFLAGS CFLAGS CXXFLAGS CPPFLAGS

 COOKBOOK_SOURCE="$COOKBOOK_SOURCE/llvm"

-# Restore the cross-compile flags for the CROSS build via cmake vars rather
-# than the environment: an exported LDFLAGS leaks into the native try_compile
-# and re-introduces the Redox libc link failure. (Native.cmake above keeps the
-# host sub-build clean.)
-if [ -n "${_SAVED_LDFLAGS}" ]; then
-    COOKBOOK_CMAKE_FLAGS+=(-DCMAKE_EXE_LINKER_FLAGS="${_SAVED_LDFLAGS}")
-    COOKBOOK_CMAKE_FLAGS+=(-DCMAKE_SHARED_LINKER_FLAGS="${_SAVED_LDFLAGS}")
-fi
-if [ -n "${_SAVED_CFLAGS}" ]; then
-    COOKBOOK_CMAKE_FLAGS+=(-DCMAKE_C_FLAGS="${_SAVED_CFLAGS}")
-fi
-# LLVM 21 REQUIRES C++17 (its headers use std::remove_reference_t, std::size,
-# std::shared_timed_mutex, etc.). The main build gets -std=gnu++17 from LLVM's
-# own CMAKE_CXX_STANDARD=17, appended after CMAKE_CXX_FLAGS so it wins — but the
-# CROSS_TOOLCHAIN_FLAGS_NATIVE sub-build (native llvm-tblgen) inherits
-# CMAKE_CXX_FLAGS with a DIFFERENT flag order where a stale "--std=gnu++11"
-# would win, breaking <shared_mutex> ("'_M_rwlock' was not declared"). Pass
-# gnu++17 here so no target can regress to C++11 regardless of flag order.
-if [ -n "${_SAVED_CXXFLAGS}" ]; then
-    COOKBOOK_CMAKE_FLAGS+=(-DCMAKE_CXX_FLAGS="--std=gnu++17 ${_SAVED_CXXFLAGS}")
-else
-    COOKBOOK_CMAKE_FLAGS+=(-DCMAKE_CXX_FLAGS="--std=gnu++17")
-fi
+"${COOKBOOK_CMAKE}" "${COOKBOOK_SOURCE}" \
+    -G Ninja \
+    -Wno-dev \
+    -DCMAKE_C_COMPILER=/usr/bin/gcc \
+    -DCMAKE_CXX_COMPILER=/usr/bin/g++ \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DCMAKE_INSTALL_PREFIX=/usr \
+    -DLLVM_ENABLE_PROJECTS="clang;lld" \
+    -DLLVM_BUILD_LLVM_DYLIB=On \
+    -DLLVM_LINK_LLVM_DYLIB=On \
+    -DLLVM_INCLUDE_UTILS=On \
+    -DLLVM_INSTALL_UTILS=On \
+    -DLLVM_TARGETS_TO_BUILD="$LLVM_HOST_ARCH" \
+    -DLLVM_ENABLE_ZLIB=Off \
+    -DLLVM_ENABLE_ZSTD=Off \
+    -DLLVM_ENABLE_LIBXML2=Off \
+    -DLLVM_ENABLE_WERROR=Off \
+    -DCLANG_LINK_CLANG_DYLIB=On \
+    -DLIBCLANG_BUILD_STATIC=1 \
+    -DBUILD_SHARED_LIBS=False \
+    -DLLVM_BUILD_EXAMPLES=Off \
+    -DLLVM_BUILD_TESTS=Off \
+    -DLLVM_INCLUDE_EXAMPLES=Off \
+    -DLLVM_INCLUDE_TESTS=Off \
+    -DLLVM_DEFAULT_TARGET_TRIPLE="${TARGET}" \
+    -DLLVM_ENABLE_LTO=Off \
+    -DLLVM_ENABLE_RTTI=On \
+    -DLLVM_ENABLE_THREADS=On \
+    -DLLVM_TARGET_ARCH="$LLVM_HOST_ARCH" \
+    -DLLVM_TOOLS_INSTALL_DIR=bin \
+    -DLLVM_UTILS_INSTALL_DIR=bin \
+    -DUNIX=1

-cookbook_cmake
+"${COOKBOOK_NINJA}" -j"${COOKBOOK_MAKE_JOBS}"
+DESTDIR="${COOKBOOK_STAGE}" "${COOKBOOK_NINJA}" install

 # Create unprefixed symlinks for native use
 for tool in clang clang++ clang-cpp clang-cl clang-check clang-format clang-tidy \
@@ -184,8 +110,8 @@ rm -f "${COOKBOOK_STAGE}"/usr/lib/*.la
 """

 [package]
-description = "Native LLVM/Clang/LLD 21 toolchain for Red Bear OS"
-dependencies = ["llvm21.runtime"]
+description = "Native (host) LLVM/Clang/LLD 21 toolchain for Red Bear OS — host build-time tool tree consumed by libclc; not shipped to the target image"
+dependencies = []

 [[optional-packages]]
 name = "dev"