I'm currently working on a criu images -> core dump conversion for CRIT(CRiu Image Tool) and while looking for some info on manually generating core dump, I've found an interesting yet outdated(OMG last changed in 2007!) project called google coredumper[1] that allows generating core dumps whenever you want to, which looks like a cool thing for a debug. CRIU is able to dump process at any point too, yet providing a lot more info about process state, because it can be literally fully restored from images, so I thought that coredump users(if there are any today) could use CRIU for their purposes. Though, criu images -> core dump conversion looks like a complete waste of data, so I have another thought on somehow integrating criu images into gdb, so it could ask criu to restore process with --leave-stopped and then attach to the process for debug. It also may be a good thing to be able to save state of the task that is being debugged by detaching and calling criu dump.
[1] https://code.google.com/p/google-coredumper/
[1] https://code.google.com/p/google-coredumper/