I had unconsciously found the workaround a few months ago while hacking around Little Snitch with kernel debugging. To make things easier I had a small GDB script to call the debug kit macros and set all the variables that are the source of the problem with gdbinit. This was something I never thought about, just accepted it.
Today, while answering to a comment, the connection was made inside my brain (I love how the brain works!) and I decided to test it. And voila, it worked!
The workaround is as simple as reloading gdbinit. You just need to issue the command source ~/.gdbinit after GDB is started either with gdb target_to_debug or inside GDB by using the file command.
And that’s it, simple things work best!