It was simpler than that: Dan created an empty directory in the GCC repository to switch to.
Ah! Googling for "gcc svn switch" took me directly to the Wiki page, which covers this; it's under setup: I didn't Google, but searched the GCC list for "svn switch". That's why I didn't find it. svn switch svn+ssh://gcc.gnu.org/svn/gcc/emptydir libada I bet that'd work. svn would treat the directory as empty and cvs would ignore the svn stuff. I'll try it. Thanks. I think you would need to do something a bit more complicated for this, using svk. Among other things, this should let you combine multiple conceptual "repositories". But I'll defer this one to our experts. Note that the gcc/ada I want would be under cvs, not svn.