https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91111
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> --- If you are looking for a workaround, perhaps replacing register long x0 asm ("x0") = (long)v; with register long x0 asm ("x0"); asm ("" : "=r" (x0) : "0" (v)); (i.e. affectively hiding from the compiler that x0 is set to v) will do the job.