https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103438
--- Comment #8 from Nils Smeds <nils.smeds at gmail dot com> --- (In reply to Nils Smeds from comment #7) > (In reply to Martin Liška from comment #6) > > Lemme take a look. > > Great, thanks. prefetch-loop-arrays appears to be activated on arm,s390 and i386 at level -O3 and higher on platforms that support software prefetch (and in the case of i386 also have TARGET_SOFTWARE_PREFETCHING_BENEFICIAL defined). For aarch64 it appears to get activated for optimization level aarch64_tune_params.prefetch->default_opt_level and higher when aarch64_tune_params.prefetch->default_opt_level is defined See: gcc/common.opt gcc/config/arm/arm.c gcc/config/i386/i386-options.c gcc/config/aarch64/aarch64.c gcc/config/s390/s390.c So it does appear to be a bug in the code path for -Q --help
