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I should build the next set of cross-compilers soon, > and will be able to retest then. Hi Arnd, thank you for sending those configs. All 4 previously failing configs were successfully built with the new patch applied (on top of 5d6919055dec (tag: v7.1-rc3, origin/master, origin/HEAD) Linux 7.1-rc3): * 0x5AB716A4 - arm64, UP (no SMP), GCOV_PROFILE_URING + GCOV_PROFILE_RDS: build OK (make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-) * 0xD01A6C73 - x86_32 (i386), SMP, GCOV_PROFILE_URING + GCOV_PROFILE_RDS: build OK (make ARCH=i386) * 0xD21DABF - arm64, UP (no SMP), GCOV_PROFILE_URING: build OK * 0xFE5738DD - x86_32 (i386), UP (no SMP), GCOV_PROFILE_URING + GCOV_PROFILE_FTRACE: build OK Previously these configs failed at link stage with undefined references to __aarch64_ldadd8_relax (arm64) and __atomic_fetch_add_8 (x86_32), caused by 64-bit atomic operations inserted by GCOV instrumentation. The new patch resolves all of these. Note: the original failures were reported with gcc-16.0.1.2-nolibc cross toolchain; my test builds used gcc-12.1.1 (aarch64-linux-gnu) and gcc-11.4.1 (x86), but i really think this does not matter here: i've checked in all 4 cases -fprofile-update=prefer-atomic was not used - try-run fence worked fine. And when i've built the 0xD01A6C73-config switched to x86_64 (# CONFIG_X86_32 is not set, CONFIG_X86_64=y and CONFIG_64BIT=y), the build passed and -fprofile-update=prefer-atomic was used. -- Thank you, Konstantin