For some reason, the Gnu readline distribution doesn't compile
out of the box on Irix (sgi boxes).  I could change the Gnu
dist to fix this, but I don't really want to...

So here's what you should do to compile tintin++ on a sgi.
First, cd to src/readline and edit Makefile.in.  Change the
line which says

DEFS = @DEFS@

to read

DEFS = @DEFS@ -D_BSD_SIGNALS

Now cd back to src/ and run

./configure
make

as normal.  This should work.  If not, please send me email
using the gripe command.  Sorry 'bout that!