I thought you had to use gcc 2.7.2 to compile the 1.3.x kernels and beyond
(at least as of some particular 1.3.x release). This was about the time the
dev teams "abandoned" a.out for ELF in the "official" releases. I don't
remember the reasons why, but an optimization bug in gcc would seem to be the
most likely reason (either the optimizer seg faults like you are reporting,
or it would generate non-working code).
kc