In the latest release CCT's SAGA C++ implementation doesn't require a set SAGA_LOCATION environment variable anymore (at least as long as the installation has not been moved from the --prefix directory it was configured and built with). If no $SAGA_LOCATION is set it internally defaults to the directory used during ./configure --prefix=... This doesn't free you from the need to properly set your LD_LIBRARY_PATH, but that's another issue, I guess.
The makefiles in LSU's SAGA C++ implementation (e.g. $SAGA_LOCATION/share/saga/make/saga.application.mk) still need either SAGA_ROOT or SAGA_LOCATION to be set. A user that writes a SAGA app using an existing SAGA C++ installation therefore still needs to set SAGA_LOCATION, otherwise he cannot include saga.application.mk in the makefile of his own application. It's not clear to me whether that's a bug or not, but it seems to conflict with the quoted statement.
That's only at build time. And no that's not a bug. If you want to use the saga makesystem you'll have to tell it where to look. Another option not requiring to have a set $SAGA_LOCATION is to use the generated saga-config script which gives you the needed commandline arguments for the compiler and linker to build a application: g++ `saga-config --cflags` -c your_saga_app.cpp g++ `saga-config --lflags` -o your_saga_app your_saga_app.o Any ready built saga application doesn't need to have the SAGA_LOCATION set (see my other post). Regards Hartmut