I am currently trying to add support for the SGI IDO (Iris Development
Option) available (for free) for IRIX 5.3.
It includes a cc, but no c++ compiler.
The options the cc accepts considerably differ from the later MIPSPro
compilers, so I think it makes sense to just start a new compiler
environment for buildlink3.
This is exactly what I did. I do not claim to fully understand
buildlink3, so I simply used the mipspro config files as a start.
Right now there are still two questions that come to my mind:

- Naming: I decided to use the term ido53 for it. To my knowledge, the
later MIPSPro development environments are also termed IDO by SGI, hence
I added the "53". I am open for any better suggestions though.
 
- SGI IDO 5.3 does not come with a C++ compiler, thus g++ has to be used
in lieu. I wonder whether all this buildlink options rewriting stuff
only refers to cc, or, if not, how it could be limited. I do not want to
rewrite g++ options, of course. More importantly, how do I specify to
use g++ (and where it can be found)? Right now, when necessary, I
specify CXX= on the command line.
So any hints form people with a better understanding of pkgsrc and
buildlink would be appreciated.

I would appreciate if someone could review my changes, so hopefully
these additions can soon make it into pkgsrc.

Thanks.

Georg

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