I thought you meant giving it relative paths in your CMakeLists.txt -- which does work as expected.

> This makes CMake-generated projects almost useless: you cannot source control them or share them in any other way.

Yes, and this is a good thing. I'm surprised anyone would want to do this on a visual studio solution of all things -- managing solution and project file merges in source control is incredibly tedious.

A lot of things about CMake irritate me, but its treatment of out of source build files as purely intermediate is a major plus to me, not a negative.

I could see how this would mess up your use case; but you have to admit your use case is very narrow -- I guess you want to be able to just rename the build folder; if you moved it more than that even the relative path to the source dir would be off -- and the justification for the limitation seems sensible.