For individual end users on personal machines (the vast majority of the "installer" community), the CMake separation of source-tree, build area, and install area is more complex than GEANT4 has traditionally been. Such users are doing a single build from the tar-ball, with only the G4 version being the level of replication. Would it be possible to provide a simple, top-level CMake option to do an in-situ build? That is, all three directories are set identically to the directory where the tar-ball was unpacked. This option (or the source == build state) should be protected against developers, so that new files created by the build are not liable for commission back into SVN.
Can probably be handled by check for .svn directory alongside CMakeLists.txt. Possible care needed to handle svn 1.7 where .svn only present in one place (though should always be next to CMakeLists.txt)
Postponing this until first patch of 9.6, as time has run out for testing this fully against all use cases (especially the changes wrought by SVN 1.7) and adding documentation for the 9.6.0 release (sincere apologies for this). I've also marked this as depending on Bug #1356, as the first step will be to improve the build directory so that build products are output into a structure replicating the final install locations - this is important to make an in-source build helpful to use.
Marking as LATER due to other higher priority issues.
Resolved since Geant4 10.3, all libs output to BuildProducts dir in build location. Fully usable by CMake/GNUMake clients by pointing them to the Geant4Config/geant4make scripts in the main build directory.
