I had that problem the other day on a new install. I had my cflags set up with several optimizations:
CFLAGS="-mcpu=750 -O3 -pipe -mpowerpc-gfxopt -mtune=750 -fno-strict-aliasing"
and I guess it was too extreme for the bootstrap, so I changed O3 to O2, removed -mpowerpc-gfxopt and -mtune=750 and it went fine. Then I added them back after the bootstrap and it went right through system and all the other apps I wanted