Hi, First; are you using the right PATH to the compilers? as in /opt/SUNWspro/bin or /usr/sfw/bin before any other path to other locations of gcc? for Sun CC I suggest; export PATH=/usr/bin:/opt/SUNWspro/bin:/usr/ccs/bin gcc: export PATH=/usr/bin:/usr/sfw/bin:/usr/ccs/binNext, when using Sun CC you must supply -xarch=amd64 for producing 64-bit amd64 version1 binaries. Also, make sure your linker i