[kbuild-all] Re: [peterz-queue:sched/core 13/19] kernel/sched/fair.c:892:34: warning: variable 'stats' set but not used

On Sat, Sep 11, 2021 at 02:21:26AM +0800, kernel test robot wrote: > compiler: m68k-linux-gcc (GCC) 11.2.0 > kernel/sched/fair.c: In function 'update_curr': > kernel/sched/fair.c:860:42: warning: unused variable 'stats' [-Wunused-variable] > 860 | struct sched_statistics *stats = __schedstats_from_se(curr); > | ^~~~~ OK, compiler guys, this code reads like: #define schedstats_enabled() (0) #define __schedstat_set(x, y) do { } while (0) if (schedstats_enabled()) { struct sched_statistics *stats = __schedstats_from_se(curr); __schedstat_set(stats->exec_max, max(delta_exec, stats->exec_max)); } So yes, we initialize a variable that then isn't used, but the whole bloody thing is inside if (0) which will not ever get ran *anyway*. This is a crap warning if ever I saw one...