Hi, with gcc:10 installed CONFIG_PLUGIN_HOSTCC is incorrectly set to an empty string instead of "g++" and therefore CONFIG_GCC_PLUGINS is disabled. CONFIG_PLUGIN_HOSTCC is set by an external helper script in scripts/gcc-plugin.sh. As I manually edited this script into echo "g++"; exit 0 the CONFIGs are correct, but compilation failes as the kernel can't find some headers like params.h in /usr/lib/gcc/x86_64-pc-linux-gnu/10.1.0/plugin/include/. I tested with gcc-10.1.0 and gcc-10.1.1_pre9999 (8275e0a6686b465d4d1717784e3e864305d37d02) and both vanilla-sources and gentoo-sources (even though it's obvious that the genpatches don't touch this area). So far the only workaround I know of is to downgrade to <=sys-devel/gcc-9.3.0 and build the kernel with it. Reproducible: Always
Upstream kernel had quite a few fixes related to plugins you might want to backport. commit 9851a0dee7c28514f149f7e4f60ec1b06286cc1b Merge: a16a47e98a30 c7527373fe28 Author: Linus Torvalds <torvalds@linux-foundation.org> Date: Mon May 4 11:20:32 2020 -0700 Merge tag 'gcc-plugins-v5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull gcc-plugins fixes from Kees Cook: "GCC 10 fixes for gcc-plugins: - Adjust caller of cgraph_create_edge for GCC 10 argument usage - Update common headers to build under GCC 10 (Frédéric Pierret)" commit c7527373fe28f97d8a196ab562db5589be0d34b9 Author: Frédéric Pierret (fepitre) <frederic.pierret@qubes-os.org> Date: Tue Apr 7 13:32:59 2020 +0200 gcc-common.h: Update for GCC 10 Remove "params.h" include, which has been dropped in GCC 10. And a ton of -Werror, -fno-common and warning fixes.
Having the same issue. Masking >sys-devel/gcc-9.3.0 fixed it for me for the time being.
Upcoming stable linux-5.6.15 should include the backport: https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/queue-5.6/gcc-common.h-update-for-gcc-10.patch Applying this patch on v5.6.14 and building with gcc-10 gives me the same result as gcc-9.3.0.
Upstream released 5.6.15 which will be probably inside the tree soon, so I do close this bug. Kernel configuration works now and compilation looks good so far, too (still in progress). [1] https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6.15
