What is ABI supposed to be set to? With IRIX, for example, I thought it
should be either "32" or "64", depending on your machine.
Now devel/gmp for example, says it expects, for IRIX 5.3, to be "o32",
if set.
So in order to get gmp compiled I had to add to Makefile:

.if !empty(LOWER_OPSYS:Mirix5*) && !empty(ABI)
ABI=                    o32
.endif

I am not sure there is a similar issue with IRIX 6 or with other OSes.

-- 
Georg Schwarz    http://home.pages.de/~schwarz/
 geos@epost.de     +49 177 8811442