https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65242
--- Comment #3 from Peter Bergner <bergner at gcc dot gnu.org> --- The debugger shows: #1 0x0000000010d0d2ec in gen_add2_insn (x=0x3fffb57ddf08, y=0x3fffb57dded8) at /home/bergner/gcc/gcc-fsf-mainline-PR65242/gcc/optabs.c:4761 4761 gcc_assert (insn_operand_matches (icode, 2, y)); (gdb) pr x (reg:DI 32 0) (gdb) pr y (mem/u/c:DI (lo_sum:DI (high:DI (unspec:DI [ (symbol_ref/u:DI ("*.LC2") [flags 0x2]) (reg:DI 2 2) ] UNSPEC_TOCREL)) (unspec:DI [ (symbol_ref/u:DI ("*.LC2") [flags 0x2]) (reg:DI 2 2) ] UNSPEC_TOCREL)) [14 S8 A64]) Talking with Mike, he said this is a fusion issue, so I'm going to leave this one for him.