On Mon, 27 Oct 2025 at 13:43, Naresh Kamboju <[email protected]> wrote: > > The following powerpc ppc6xx_defconfig build regressions noticed on the > Linux next-20251027 tag with gcc-14 and gcc-8. > > * powerpc, build > - gcc-14-ppc6xx_defconfig > - gcc-8-ppc6xx_defconfig > > First seen on next-20251027 > Good: next-20251024 > Bad: next-20251027 > > Regression Analysis: > - New regression? yes > - Reproducibility? yes > > Build regression: next-20251027: backlight.c:59:39: error: implicit > declaration of function 'of_find_node_by_name'; did you mean > 'bus_find_device_by_name'? > Build regression: next-20251027: include/linux/math.h:167:43: error: > first argument to '__builtin_choose_expr' not a constant > Build regression: next-20251027: via-pmu-backlight.c:22:20: error: > 'FB_BACKLIGHT_LEVELS' undeclared here (not in a function) > Build regression: next-20251027: minmax.h:71:17: error: first argument > to '__builtin_choose_expr' not a constant > Build regression: next-20251027: compiler.h:168:17: error: > '__UNIQUE_ID_x__286' undeclared (first use in this function); did you > mean '__UNIQUE_ID_y__287'?
Anders bisected this down to, # first bad commit: [243ce64b2b371cdf2cbc39c9422cb3047cab6de7] backlight: Do not include <linux/fb.h> in header file > > Reported-by: Linux Kernel Functional Testing <[email protected]> > > ## Build error > arch/powerpc/platforms/powermac/backlight.c: In function > 'pmac_has_backlight_type': > arch/powerpc/platforms/powermac/backlight.c:59:39: error: implicit > declaration of function 'of_find_node_by_name'; did you mean > 'bus_find_device_by_name'? [-Wimplicit-function-declaration] > 59 | struct device_node* bk_node = > of_find_node_by_name(NULL, "backlight"); > | ^~~~~~~~~~~~~~~~~~~~ > | bus_find_device_by_name > arch/powerpc/platforms/powermac/backlight.c:59:39: error: > initialization of 'struct device_node *' from 'int' makes pointer from > integer without a cast [-Wint-conversion] > arch/powerpc/platforms/powermac/backlight.c:60:17: error: implicit > declaration of function 'of_property_match_string' > [-Wimplicit-function-declaration] > 60 | int i = of_property_match_string(bk_node, > "backlight-control", type); > | ^~~~~~~~~~~~~~~~~~~~~~~~ > arch/powerpc/platforms/powermac/backlight.c:62:9: error: implicit > declaration of function 'of_node_put' > [-Wimplicit-function-declaration] > 62 | of_node_put(bk_node); > | ^~~~~~~~~~~ > drivers/macintosh/via-pmu-backlight.c:22:20: error: > 'FB_BACKLIGHT_LEVELS' undeclared here (not in a function) > 22 | static u8 bl_curve[FB_BACKLIGHT_LEVELS]; > | ^~~~~~~~~~~~~~~~~~~ > In file included from <command-line>: > drivers/macintosh/via-pmu-backlight.c: In function > 'pmu_backlight_curve_lookup': > include/linux/compiler.h:168:17: error: '__UNIQUE_ID_x__286' > undeclared (first use in this function); did you mean > '__UNIQUE_ID_y__287'? > 168 | __PASTE(__UNIQUE_ID_, \ > | ^~~~~~~~~~~~ > drivers/macintosh/via-pmu-backlight.c:45:23: note: in expansion of macro 'max' > 45 | max = max((int)bl_curve[i], max); > | ^~~ > include/linux/minmax.h:71:17: error: first argument to > '__builtin_choose_expr' not a constant > 71 | (typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, > 1L)))(ux) >= 0) > | ^~~~~~~~~~~~~~~~~~~~~ > include/linux/compiler_types.h:577:23: note: in definition of macro > '__compiletime_assert' > 577 | if (!(condition)) > \ > | ^~~~~~~~~ > drivers/macintosh/via-pmu-backlight.c:45:23: note: in expansion of macro 'max' > 45 | max = max((int)bl_curve[i], max); > | ^~~ > include/linux/minmax.h:71:17: error: first argument to > '__builtin_choose_expr' not a constant > 71 | (typeof(__builtin_choose_expr(sizeof(ux) > 4, 1LL, > 1L)))(ux) >= 0) > | ^~~~~~~~~~~~~~~~~~~~~ > include/linux/compiler_types.h:577:23: note: in definition of macro > '__compiletime_assert' > 577 | if (!(condition)) > \ > | ^~~~~~~~~ > include/linux/minmax.h:112:25: note: in expansion of macro '__careful_cmp' > 112 | #define max(x, y) __careful_cmp(max, x, y) > | ^~~~~~~~~~~~~ > drivers/macintosh/via-pmu-backlight.c:45:23: note: in expansion of macro 'max' > 45 | max = max((int)bl_curve[i], max); > | ^~~ > In file included from include/linux/kernel.h:27, > from arch/powerpc/include/asm/page.h:11, > from arch/powerpc/include/asm/thread_info.h:13, > from include/linux/thread_info.h:60, > from arch/powerpc/include/asm/ptrace.h:342, > from drivers/macintosh/via-pmu-backlight.c:11: > include/linux/math.h:162:17: error: first argument to > '__builtin_choose_expr' not a constant > 162 | __builtin_choose_expr( > \ > | ^~~~~~~~~~~~~~~~~~~~~ > > drivers/macintosh/via-pmu-backlight.c: In function > 'pmu_backlight_get_level_brightness': > drivers/macintosh/via-pmu-backlight.c:63:38: error: 'FB_BACKLIGHT_MAX' > undeclared (first use in this function); did you mean 'BACKLIGHT_RAW'? > 63 | pmulevel = bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL; > | ^~~~~~~~~~~~~~~~ > | BACKLIGHT_RAW > drivers/macintosh/via-pmu-backlight.c:58:51: warning: parameter > 'level' set but not used [-Wunused-but-set-parameter] > 58 | static int pmu_backlight_get_level_brightness(int level) > | ~~~~^~~~~ > drivers/macintosh/via-pmu-backlight.c: In function 'pmu_backlight_init': > drivers/macintosh/via-pmu-backlight.c:144:17: error: implicit > declaration of function 'of_machine_is_compatible' > [-Wimplicit-function-declaration] > 144 | of_machine_is_compatible("AAPL,3400/2400") || > | ^~~~~~~~~~~~~~~~~~~~~~~~ > drivers/macintosh/via-pmu-backlight.c: At top level: > drivers/macintosh/via-pmu-backlight.c:22:11: warning: 'bl_curve' > defined but not used [-Wunused-variable] > 22 | static u8 bl_curve[FB_BACKLIGHT_LEVELS]; > | ^~~~~~~~ > make[5]: *** [scripts/Makefile.build:287: > drivers/macintosh/via-pmu-backlight.o] Error 1 > make[5]: Target 'drivers/macintosh/' not remade because of errors. > > > ## Source > * Kernel version: 6.18.0-rc2-next-20251027 > * Git tree: > https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git > * Git describe: next-20251027 > * Git commit: 8fec172c82c2b5f6f8e47ab837c1dc91ee3d1b87 > * Architectures: powerpc > * Toolchains: gcc-14 > * Kconfigs: defconfig > > ## Build > * Test log: > https://storage.tuxsuite.com/public/linaro/lkft/builds/34dKrlb77LGOQQSoC8FHCiIEAZK/build.log > * Test details: > https://regressions.linaro.org/lkft/linux-next-master/next-20251027/build/gcc-14-ppc6xx_defconfig/ > * Build plan: > https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/builds/34dKrlb77LGOQQSoC8FHCiIEAZK > * Build link: > https://storage.tuxsuite.com/public/linaro/lkft/builds/34dKrlb77LGOQQSoC8FHCiIEAZK/ > * Kernel config: > https://storage.tuxsuite.com/public/linaro/lkft/builds/34dKrlb77LGOQQSoC8FHCiIEAZK/config > > -- > Linaro LKFT - Naresh
