I have very fond memories of the good old SGI days. Build vs target env gcc vs cc GNU configure and autoconf GNU autoconf generates configure scripts which make the wrong assumption that if a library exists, it should be used. This is incorrect on IRIX which keeps some old libraries around just for the sake of backward compatibility with very old programs. To prevent this from happening, simply force GNU configure to explicitly ignore 'libsocket', 'libnsl', 'libgen', and 'libsun'.
Compatibility is good.
If you Makefile calls ranlib either delete this or define it to a no-op. Mixing signal models may cause unpredictable problems. The SGI cc is verbose and pedantic. The problem is that when you get way too may warnings you start ignoring the real ones. While the SGI cc may look too pedantic, it can catch a lot of real source code bugs.