http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54983
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-10-19 11:01:13 UTC --- I think there might be an issue with some of the inline-asm in asm/io.h: static inline __attribute__((always_inline)) __attribute__((no_instrument_function)) void __raw_writew(u16 val, volatile void *addr) { asm volatile("strh %1, %0" : "+Qo" (*(volatile u16 *)addr) : "r" (val)); Also what options are being passed to the gcc?