1) gdb will be depricated in future releases, and
GDB will be removed from FreeBSD base once Clang/LLVM / LLDB matures (and probably once 99% of ports compile with it). But no, it wont be deprecated. A simple
pkg install gdb
will be all that is needed.
I generally don't use GUI debuggers but I believe Insight (if it exists in the ports collection) is pretty much libXt only. At the very worst, libXm.
It is odd though.. I have never really found gdb to be that flaky. What version are you using? Perhaps try the latest gdb from ports. Remember, the one in base is pretty ancient (with patches) due to the less permissive licensing of GPL.
Again, depending on your version (i.e on 7.1), try compiling with
-Og. I personally have always got away with specifying no
-O option when
-g is specified but your usecase may differ.
"some compiler passes that collect information useful for debugging do not run at all, so that -Og may result in a better debugging experience." - GCC manpage.