The following build warnings / errors noticed on arm riscv mips with gcc-8 toolchain but gcc-13 build pass for the following configs.

Regression Analysis: - New regression? yes - Reproducibility? yes

First seen on next-20250826 Good: next-20250825 Bad: next-20250826 to next-20250828

Build regression: next-20250826 gcc-8 compiler_types.h:572:38: error: call to '__compiletime_assert_478' declared with attribute error: FIELD_PREP: value too large for the field

Reported-by: Linux Kernel Functional Testing lkft@linaro.org

arm: build: * gcc-8-integrator_defconfig * gcc-8-omap1_defconfig * gcc-8-footbridge_defconfig

riscv: build: * gcc-8-defconfig * gcc-8-lkftconfig-hardening

mips: * cavium_octeon_defconfig * malta_defconfig * defconfig

## Build log drivers/pci/pci.c: In function 'pcie_set_readrq': include/linux/compiler_types.h:572:38: error: call to '__compiletime_assert_478' declared with attribute error: FIELD_PREP: value too large for the field _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^

Anders bisected this and found, # first bad commit: [cbc654d18d3743cff70b2dafb64c903b8cd01f2b] bitops: Add __attribute_const__ to generic ffs()-family implementations

## Source * Kernel version: 6.17.0-rc3-next-20250828 * Git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git * Git describe: next-20250828 * Architectures: arm riscv mips * Toolchains: gcc-8 * Kconfigs: integrator_defconfig, omap1_defconfig, footbridge_defconfig

## Build * Build log: https://qa-reports.linaro.org/api/testruns/29694807/log_file/ * Build details: https://regressions.linaro.org/lkft/linux-next-master/next-20250828/build/gc... * Build error details: https://regressions.linaro.org/lkft/linux-next-master/next-20250828/log-pars... * Build plan: https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/builds/31u6OUKGnk... * Build link: https://storage.tuxsuite.com/public/linaro/lkft/builds/31u6OUKGnkxZYEIbLMDV9... * Kernel config: https://storage.tuxsuite.com/public/linaro/lkft/builds/31u6OUKGnkxZYEIbLMDV9...

-- Linaro LKFT https://lkft.linaro.org