https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58306
--- Comment #42 from PeteVine <tulipawn at gmail dot com> --- Funnily enough, using `-fprofile-update=atomic` and targeting Cortex-A5/NEON immediately leads to a hard-freeze on trying to run the instrumented binary. Probably a bug in the outdated kernel. (I've got a screenshot of the xterm session if anybody's interested)