From: Zeugswetter Andreas Wed Nov 8 11:16:35 MEZ 2000 AIX 4.3.2 with native IBM compiler xlc 3.6.4 passes all regression tests. Other versions of OS and compiler should also work. If you don't have a powerpc there might be differences in the geometry regression test. Use the following configure flags in addition to your own if you have readline or libz there: --with-includes=/usr/local/include --with-libraries=/usr/local/lib libpq++ does not work because xlC does not have the string and bool classes. compiling the few files, that fail, with g++ does work. Compiling PostgreSQL with gcc (2.95.2) on AIX also works. There will probably be warnings about int8 - int64 redefines, 0.0/0.0 division and duplicate symbol warnings which you can safely ignore.