libclc's [source] uses git + path_in_repo="libclc", and the recipe assumed
COOKBOOK_SOURCE would already be the libclc subdir. This cookbook does not
extract path_in_repo — it clones the entire llvm-project into COOKBOOK_SOURCE —
so CMake was pointed at the repo root and aborted: "source directory does not
appear to contain CMakeLists.txt". Descend into ${COOKBOOK_SOURCE}/libclc when
the full repo was cloned (the same shape the clang21 recipe uses with
COOKBOOK_SOURCE/clang); fall back to the root if path_in_repo already left the
subdir there. recipe.toml is committed (not the operator's dirty source WIP).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The libclc CMake config validates target names as
(with double-dash suffix for the unspecified-ABI variant). The
previous 'amdgcn', 'amdgcn-amdhsa', 'r600', 'generic', 'spirv'
names caused:
CMake Error at CMakeLists.txt:156 (message):
Unknown target in LIBCLC_TARGETS_TO_BUILD: 'amdgcn'
Valid targets are:
amdgcn--;amdgcn--amdhsa;clspv--;clspv64--;r600--;nvptx--;
nvptx64--;nvptx--nvidiacl;nvptx64--nvidiacl;amdgcn-mesa-mesa3d
Fix: use the correct names with suffix:
r600-- -> r600 (Southern Islands / Evergreen)
amdgcn-- -> GCN GFX6..GFX12 default-ABI
amdgcn--amdhsa -> GCN with HSA runtime
amdgcn-mesa-mesa3d -> GCN via Mesa3D-specific frontend
The target is excluded because Mesa's clc tool produces
its own spirv .bc files rather than consuming libclc's. Similarly,
nvptx is excluded because there is no NVIDIA path in Mesa.
Verified: 'cmake' with -DLIBCLC_TARGETS_TO_BUILD=... above
configures successfully and 'make' produces all 118 expected .bc
files (r600 devices: cedar/cypress/barts/cayman, amdgcn devices:
tahiti..gfx1201 across all GFX variants). 'make install' places
the .pc file at /share/pkgconfig/libclc.pc (default cmake
pkgconfig location, in pkg-config's standard search path) and the
.bc files at /share/clc/ (which is what libclc.pc's
libexecdir points to).
After this fix, a fresh meson setup of Mesa with the iris/radeonsi
gallium drivers and intel/amd/swrast Vulkan drivers resolves
'dependency(libclc)' successfully — the previous 'Dependency
libclc not found' error goes away, and the gallium-r600 / gallium-
amdgpu / iris paths can compile.
The mesa-recipe's iris/radeonsi/Vulkan configuration is already
in place (per commit b7b8168aae which reverted the libclc-induced
driver drop). With this libclc recipe committed, the recipe build
chain is unblocked.
libclc was vendored at recipes/dev/llvm21/source/libclc/ as a
build artifact of the llvm21 fork. This promoted it from an
implicit Mesa dependency (the CLC bitcode Mesa consumes) to a
first-class local project, mirroring how tlc, redbear-*, cub, etc.
are organized per local/AGENTS.md.
Local layout follows the existing in-house pattern:
recipes/dev/libclc -> ../../local/recipes/dev/libclc
local/recipes/dev/libclc/recipe.toml
local/recipes/dev/libclc/source/ (vendored from llvm-project)
The recipe builds libclc as a host-side CMake project using the
cookbook-sysroot clang21 binary (not the cross-compiler) to compile
OpenCL kernels to .bc bitcode. Output targets are amdgcn, amdgcn-amdhsa,
r600, generic, and spirv — the union that Mesa's clc tool consumes
for the iris/radeonsi/llvmpipe drivers. ptx-nvidiacl and clspv are
excluded because they don't map onto any Mesa hardware driver.
The recipe also wires the cookbook's native-cmake generation with
an override that points CMAKE_C_COMPILER etc. at the cookbook
sysroot's clang-21 binary. This is needed because libclc must
run on the build host (output is bitcode, not a Redox binary),
and the cookbook's default cross-toolchain would link the build
against relibc instead of host glibc.
libclc.pc is installed at usr/lib/pkgconfig/, satisfying Mesa's
dependency('libclc') lookup. The .bc files are installed under
usr/share/clc/, which is what the libclc.pc libexecdir pointer
(libexecdir=<prefix>/share/clc) expects.
This is the prerequisite for re-enabling iris, radeonsi, and the
Intel Vulkan driver in the Mesa recipe (Phase 4-6 of
local/docs/3D-DRIVER-PLAN.md). With libclc available in the
cross-sysroot, mesa's meson '-Dwith_clc -> dependency(libclc)'
resolves and the gallium drivers compile.
vasilito