http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52472
--- Comment #4 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2012-03-05 14:05:36 UTC --- I tried #define POINTERS_EXTEND_UNSIGNED 1 but this runs into ICE some lines later in cfgexpand.c:2496 mode = PSI as = 0 x = symbol_ref:PSI ("data") Of course PSImode is not a valid pointer mode for generic address space.