classes: add oneapi-vendor-compat bbclass

The Intel oneAPI DPC++/C++ compiler binaries (icx, icpx) shipped by
meta-intel as prebuilt installers have a fixed default -target triple
baked into the LLVM driver. As of the 2025.3.x bundle the triple is
'x86_64-unknown-linux-gnu' (LLVM's portable default); prior 2024.x
bundles used 'x86_64-oe-linux' (matching the OpenEmbedded nodistro
default of TARGET_VENDOR=oe). icx also emits 'x86_64-linux-gnu' (the
Debian/Ubuntu host triple) in some search paths.

Yocto distros set TARGET_VENDOR differently: poky uses 'poky'
(TARGET_SYS=x86_64-poky-linux), nodistro uses 'oe', etc. The result
is a vendor-triple mismatch: icx looks for crtbeginS.o /
bits/c++config.h and similar files under one triple while they are
installed at another.

Until Intel either ships per-vendor variants or the meta-intel oneAPI
recipes patch the prebuilt binaries, install a set of compatibility
symlinks at rootfs time so every spelling of the multilib vendor
triple resolves to the same files on the image. The alias set is
configurable via ONEAPI_VENDOR_TRIPLE_ALIASES; entries that already
match the native target triple are skipped, so the class is a no-op
on images whose native vendor matches every alias.

Usage: add to IMAGE_CLASSES in a distro / local config that consumes
the Intel oneAPI compiler:

    IMAGE_CLASSES += "oneapi-vendor-compat"

Signed-off-by: Yogesh Tyagi <yogesh.tyagi@intel.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/classes/oneapi-vendor-compat.bbclass b/classes/oneapi-vendor-compat.bbclass
new file mode 100644
index 00000000..49776d22
--- /dev/null
+++ b/classes/oneapi-vendor-compat.bbclass
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: MIT
+#
+# oneapi-vendor-compat.bbclass
+#
+# The Intel oneAPI DPC++/C++ compiler binaries (icx, icpx) shipped by
+# meta-intel as prebuilt installers have a fixed default ``-target`` triple
+# baked into the LLVM driver. As of the 2025.3.x bundle the triple is
+# ``x86_64-unknown-linux-gnu`` (LLVM's portable default); prior bundles used
+# ``x86_64-oe-linux`` (matching the OpenEmbedded ``nodistro`` default of
+# ``TARGET_VENDOR=oe``).
+#
+# Yocto distros set ``TARGET_VENDOR`` differently: poky uses ``poky``
+# (TARGET_SYS=``x86_64-poky-linux``), nodistro uses ``oe``, etc. The result
+# is a vendor-triple mismatch: icx looks for ``crtbeginS.o`` /
+# ``bits/c++config.h`` and similar files under one triple while they are
+# installed at another.
+#
+# Until Intel either ships per-vendor variants or the meta-intel oneAPI
+# recipes patch the prebuilt binaries, this class installs a set of
+# compatibility symlinks at rootfs time so every spelling of the multilib
+# vendor triple resolves to the same files on the image. The class is a
+# no-op when the native vendor triple already matches every alias.
+#
+# Usage: add to IMAGE_CLASSES in a distro / local config that consumes
+# the Intel oneAPI compiler::
+#
+#     IMAGE_CLASSES += "oneapi-vendor-compat"
+#
+
+# Native triple as provided by Yocto for the target sysroot.
+ONEAPI_VENDOR_TRIPLE_NATIVE ?= "${TARGET_SYS}"
+
+# Aliases icx may resolve at runtime, in priority order:
+#   - x86_64-unknown-linux-gnu : LLVM portable default (oneAPI 2025.x)
+#   - x86_64-linux-gnu         : Debian/Ubuntu host triple (icx -v output)
+#   - x86_64-oe-linux          : OE nodistro (oneAPI 2024.x)
+ONEAPI_VENDOR_TRIPLE_ALIASES ?= " \
+    ${TARGET_ARCH}-unknown-${TARGET_OS} \
+    ${TARGET_ARCH}-${TARGET_OS}-gnu \
+    ${TARGET_ARCH}-oe-${TARGET_OS} \
+"
+
+oneapi_vendor_compat_rootfs() {
+    native="${ONEAPI_VENDOR_TRIPLE_NATIVE}"
+
+    for alias in ${ONEAPI_VENDOR_TRIPLE_ALIASES}; do
+        if [ "${alias}" = "${native}" ]; then
+            continue
+        fi
+
+        # gcc multilib library tree (crt*.o, libgcc.a, etc).
+        if [ -d "${IMAGE_ROOTFS}/usr/lib/${native}" ] && \
+           [ ! -e "${IMAGE_ROOTFS}/usr/lib/${alias}" ]; then
+            ln -s "${native}" \
+                  "${IMAGE_ROOTFS}/usr/lib/${alias}"
+        fi
+
+        # multilib-aware C headers (e.g. asm/unistd_64.h).
+        if [ -d "${IMAGE_ROOTFS}/usr/include/${native}" ] && \
+           [ ! -e "${IMAGE_ROOTFS}/usr/include/${alias}" ]; then
+            ln -s "${native}" \
+                  "${IMAGE_ROOTFS}/usr/include/${alias}"
+        fi
+
+        # libstdc++ vendor-keyed bits (bits/c++config.h, ext/*.h).
+        for cxxdir in "${IMAGE_ROOTFS}/usr/include/c++/"*/ ; do
+            if [ -d "${cxxdir}/${native}" ] && \
+               [ ! -e "${cxxdir}/${alias}" ]; then
+                ln -s "${native}" \
+                      "${cxxdir}/${alias}"
+            fi
+        done
+    done
+}
+
+ROOTFS_POSTPROCESS_COMMAND:append = " oneapi_vendor_compat_rootfs;"