[PATCH v2 3/3] mesa, mesa-tools-native: Use mesa-libclc

["Zoltán Böszörményi" <zboszor@gmail.com>]

Backport two patches from
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/43020
to use mesa-libclc, which makes Rusticl's OpenCL C more correct.

Signed-off-by: Zoltán Böszörményi <zboszor@gmail.com>
---
 ...-optional-for-configs-not-needing-it.patch | 123 ++++++++++++++++++
 ...lc-use-our-downstream-fork-of-libclc.patch |  43 ++++++
 .../mesa/mesa-tools-native.bb                 |   2 +-
 meta/recipes-graphics/mesa/mesa.inc           |   6 +-
 4 files changed, 171 insertions(+), 3 deletions(-)
 create mode 100644 meta/recipes-graphics/mesa/files/0001-clc-make-libclc-optional-for-configs-not-needing-it.patch
 create mode 100644 meta/recipes-graphics/mesa/files/0002-clc-use-our-downstream-fork-of-libclc.patch

diff --git a/meta/recipes-graphics/mesa/files/0001-clc-make-libclc-optional-for-configs-not-needing-it.patch b/meta/recipes-graphics/mesa/files/0001-clc-make-libclc-optional-for-configs-not-needing-it.patch
new file mode 100644
index 0000000000..a52931dbf5
--- /dev/null
+++ b/meta/recipes-graphics/mesa/files/0001-clc-make-libclc-optional-for-configs-not-needing-it.patch
@@ -0,0 +1,123 @@
+From 5df2fb59c32fd6e3ad53bdaf98afccfddbdd14fc Mon Sep 17 00:00:00 2001
+From: Karol Herbst <kherbst@redhat.com>
+Date: Fri, 17 Jul 2026 17:45:45 +0200
+Subject: [PATCH 1/2] clc: make libclc optional for configs not needing it
+
+Upstream-Status: Submitted [https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/43020]
+---
+ meson.build                  |  2 +-
+ src/compiler/clc/meson.build | 73 +++++++++++++++++++-----------------
+ 2 files changed, 39 insertions(+), 36 deletions(-)
+
+diff --git a/meson.build b/meson.build
+index 1eca91fc940..68bbb942b99 100644
+--- a/meson.build
++++ b/meson.build
+@@ -949,7 +949,7 @@ with_poly = [
+ ].contains(true)
+ 
+ dep_clc = null_dep
+-if with_clc
++if with_gallium_rusticl or with_microsoft_clc
+   dep_clc = dependency('libclc')
+ endif
+ 
+diff --git a/src/compiler/clc/meson.build b/src/compiler/clc/meson.build
+index 9ff61440f0d..249fd31f478 100644
+--- a/src/compiler/clc/meson.build
++++ b/src/compiler/clc/meson.build
+@@ -4,7 +4,6 @@
+ files_libmesaclc = files(
+   'clc.c',
+   'clc_helpers.cpp',
+-  'nir_load_libclc.c',
+ )
+ 
+ _libmesaclc_c_args = []
+@@ -41,45 +40,49 @@ if not _shared_llvm or \
+   _libmesaclc_cpp_args += ['-DUSE_STATIC_OPENCL_C_H=1']
+ endif
+ 
+-_basedir = dep_clc.get_variable(pkgconfig : 'libexecdir')
++if dep_clc.found()
++  files_libmesaclc += 'nir_load_libclc.c'
+ 
+-_static_libclc = get_option('static-libclc')
+-if _static_libclc.length() > 0
+-  if _static_libclc.contains('all')
+-    _static_libclc = ['spirv', 'spirv64']
+-  endif
+-  prog_zstd = find_program('zstd', required : false, native : true)
+-  _zstd_static_libclc = dep_zstd.found() and prog_zstd.found()
+-  if _zstd_static_libclc
+-    _libmesaclc_c_args += '-DHAVE_STATIC_LIBCLC_ZSTD'
+-  endif
+-  foreach s : _static_libclc
+-    _libmesaclc_c_args += '-DHAVE_STATIC_LIBCLC_@0@'.format(s.to_upper())
+-    f = '@0@-mesa3d-.spv'.format(s)
+-    _libclc_file = _basedir / f
++  _basedir = dep_clc.get_variable(pkgconfig : 'libexecdir')
++
++  _static_libclc = get_option('static-libclc')
++  if _static_libclc.length() > 0
++    if _static_libclc.contains('all')
++      _static_libclc = ['spirv', 'spirv64']
++    endif
++    prog_zstd = find_program('zstd', required : false, native : true)
++    _zstd_static_libclc = dep_zstd.found() and prog_zstd.found()
+     if _zstd_static_libclc
+-      _libclc_file = custom_target(
+-        '@0@.zstd'.format(f),
+-        command : [prog_zstd, '-f', '@INPUT@', '-o', '@OUTPUT@'],
++      _libmesaclc_c_args += '-DHAVE_STATIC_LIBCLC_ZSTD'
++    endif
++    foreach s : _static_libclc
++      _libmesaclc_c_args += '-DHAVE_STATIC_LIBCLC_@0@'.format(s.to_upper())
++      f = '@0@-mesa3d-.spv'.format(s)
++      _libclc_file = _basedir / f
++      if _zstd_static_libclc
++        _libclc_file = custom_target(
++          '@0@.zstd'.format(f),
++          command : [prog_zstd, '-f', '@INPUT@', '-o', '@OUTPUT@'],
++          input : [_libclc_file],
++          output : '@0@.zstd'.format(f),
++        )
++      endif
++      files_libmesaclc += custom_target(
++        '@0@.h'.format(f),
++        command : [
++          prog_python, files_xxd, '-b', '@INPUT@', '@OUTPUT@',
++          '-n', 'libclc_@0@_mesa3d_spv'.format(s),
++        ],
+         input : [_libclc_file],
+-        output : '@0@.zstd'.format(f),
++        output : '@0@.h'.format(f),
++        depend_files : files_xxd,
+       )
++    endforeach
++  else
++    _libmesaclc_c_args += ['-DDYNAMIC_LIBCLC_PATH="@0@/"'.format(_basedir)]
++    if not cc.has_function('mmap')
++      error('mmap required for dynamic libCLC loading')
+     endif
+-    files_libmesaclc += custom_target(
+-      '@0@.h'.format(f),
+-      command : [
+-        prog_python, files_xxd, '-b', '@INPUT@', '@OUTPUT@',
+-        '-n', 'libclc_@0@_mesa3d_spv'.format(s),
+-      ],
+-      input : [_libclc_file],
+-      output : '@0@.h'.format(f),
+-      depend_files : files_xxd,
+-    )
+-  endforeach
+-else
+-  _libmesaclc_c_args += ['-DDYNAMIC_LIBCLC_PATH="@0@/"'.format(_basedir)]
+-  if not cc.has_function('mmap')
+-    error('mmap required for dynamic libCLC loading')
+   endif
+ endif
+ 
+-- 
+2.55.0
+
diff --git a/meta/recipes-graphics/mesa/files/0002-clc-use-our-downstream-fork-of-libclc.patch b/meta/recipes-graphics/mesa/files/0002-clc-use-our-downstream-fork-of-libclc.patch
new file mode 100644
index 0000000000..39e120b036
--- /dev/null
+++ b/meta/recipes-graphics/mesa/files/0002-clc-use-our-downstream-fork-of-libclc.patch
@@ -0,0 +1,43 @@
+From 8bda7974958e5ba56b0eec25a7876c004b6b743b Mon Sep 17 00:00:00 2001
+From: Karol Herbst <kherbst@redhat.com>
+Date: Thu, 16 Jul 2026 21:20:52 +0200
+Subject: [PATCH 2/2] clc: use our downstream fork of libclc
+
+There are a couple of issues with the upstream versions and release
+schedules and overall experience makes it dificult for us to rely on
+users using a proper functional implementation.
+
+And we want to ship a conformant OpenCL implementation here and that's
+difficult if users run untested libclc versions or libclc with known bugs
+that aren't going to get fixed upstream because the release is already
+EoL.
+
+Backport-to: *
+Upstream-Status: Submitted [https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/43020]
+---
+ meson.build | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+diff --git a/meson.build b/meson.build
+index 68bbb942b99..6e2590cc2c6 100644
+--- a/meson.build
++++ b/meson.build
+@@ -950,7 +950,14 @@ with_poly = [
+ 
+ dep_clc = null_dep
+ if with_gallium_rusticl or with_microsoft_clc
+-  dep_clc = dependency('libclc')
++  dep_clc = dependency('mesa-libclc', required : false,
++    not_found_message :
++    'mesa-libclc not found. Build will fall back to upstream libclc, however ' +
++    'certain versions are known to contain bugs that make OpenCL builtins ' +
++    'return incorrect results.')
++  if not dep_clc.found()
++    dep_clc = dependency('libclc')
++  endif
+ endif
+ 
+ gl_pkgconfig_c_flags = []
+-- 
+2.55.0
+
diff --git a/meta/recipes-graphics/mesa/mesa-tools-native.bb b/meta/recipes-graphics/mesa/mesa-tools-native.bb
index 20207450bf..c495d2e8a8 100644
--- a/meta/recipes-graphics/mesa/mesa-tools-native.bb
+++ b/meta/recipes-graphics/mesa/mesa-tools-native.bb
@@ -11,7 +11,7 @@ PACKAGECONFIG += "gallium-llvm"
 # to PACKAGECONFIG like in mesa.inc
 PACKAGECONFIG += "${@bb.utils.filter('DISTRO_FEATURES', 'x11 wayland', d)}"
 
-DEPENDS += "libclc-native spirv-tools-native spirv-llvm-translator-native"
+DEPENDS += "mesa-libclc-native spirv-tools-native spirv-llvm-translator-native"
 
 EXTRA_OEMESON += " \
     -Dmesa-clc=enabled -Dinstall-mesa-clc=true -Dmesa-clc-bundle-headers=enabled \
diff --git a/meta/recipes-graphics/mesa/mesa.inc b/meta/recipes-graphics/mesa/mesa.inc
index 15d56c804d..dea7a8295f 100644
--- a/meta/recipes-graphics/mesa/mesa.inc
+++ b/meta/recipes-graphics/mesa/mesa.inc
@@ -21,6 +21,8 @@ SRC_URI = "https://archive.mesa3d.org/mesa-${PV}.tar.xz \
            file://0001-src-intel-compiler-jay-jay_ir.h-do-not-used-typed-en.patch \
            file://0001-src-intel-compiler-jay-fix-GCC-10-case-label-declara.patch \
            file://0001-src-util-u_math.c-do-not-use-arm-fpu-instructions-if.patch \
+           file://0001-clc-make-libclc-optional-for-configs-not-needing-it.patch \
+           file://0002-clc-use-our-downstream-fork-of-libclc.patch \
            "
 
 SRC_URI[sha256sum] = "79e421c7ce18cd9e790b8375920325779f10798630bf30e0b22f1a21c8617122"
@@ -110,7 +112,7 @@ PACKAGECONFIG[opengl] = "-Dopengl=true, -Dopengl=false"
 
 # "opencl" also requires libclc and gallium-llvm to be present in PACKAGECONFIG!
 # Be sure to enable them both for the target and for the native build.
-PACKAGECONFIG[opencl] = "-Dgallium-rusticl=true -Dmesa-clc-bundle-headers=enabled, -Dgallium-rusticl=false, bindgen-cli-native clang libclc spirv-tools spirv-llvm-translator"
+PACKAGECONFIG[opencl] = "-Dgallium-rusticl=true -Dmesa-clc-bundle-headers=enabled, -Dgallium-rusticl=false, bindgen-cli-native clang mesa-libclc spirv-tools spirv-llvm-translator"
 
 X11_DEPS = "xorgproto virtual/libx11 libxext libxxf86vm libxdamage libxfixes xrandr xorgproto libxshmfence"
 # "x11" requires "opengl"
@@ -254,7 +256,7 @@ RPROVIDES:libopencl-mesa += "virtual-opencl-icd"
 RPROVIDES:libgles2-mesa += "libgles3-mesa"
 RPROVIDES:libgles2-mesa-dev += "libgles3-mesa-dev"
 
-RDEPENDS:libopencl-mesa += "${@bb.utils.contains('PACKAGECONFIG', 'opencl', 'libclc', '', d)}"
+RDEPENDS:libopencl-mesa += "${@bb.utils.contains('PACKAGECONFIG', 'opencl', 'mesa-libclc', '', d)}"
 
 PACKAGES =+ "libegl-mesa libegl-mesa-dev \
              libgallium \
-- 
2.55.0