Ensure that the following directories exist (otherwise create them)
${MYAIPS2ROOT}/sun4sol_gnu
${MYAIPS2ROOT}/sun4sol_gnu/aux
${MYAIPS2ROOT}/sun4sol_gnu/bin
${MYAIPS2ROOT}/sun4sol_gnu/lib
${MYAIPS2ROOT}/sun4sol_gnu/bindbg
${MYAIPS2ROOT}/sun4sol_gnu/libdbg
where $MYAIPS2ROOT is the root of your workspace.
(eg. $HOME/aips++).
At Socorro where the code is on one partition and the executables are on another (which is not backed up), you should substitute for $MYAIPS2ROOT the path /tarzan2/$USERNAME, and create a symbolic link pointing from /tarzan/$USERNAME/sun4sol_gnu to /tarzan2/$USERNAME/sun4sol_gnu