https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38629
--- Comment #8 from Federico Fissore <federico at fsfe dot org> --- I forgot to say: this result came out of avr-gcc 4.8.1 (packaged by Arduino: it's a 4.8.1 with two small patches applied [1]). It uses -Os optimization flag [1] https://github.com/arduino/toolchain-avr/tree/master/gcc-patches
