https://gcc.gnu.org/bugzilla/show_bug.cgi?id=31386
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID --- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Invalid as mentioned, you need the early clobbers, otherwise GCC thinks the output and input registers can be the same. In this case the output registers which is held in operand 0 has to be different from operands 4 and 5.