Minimum version of gdb supported?

First off, my use case is to debug arm-none-eabi executables (bare-metal ARM code) in a simulated ARM environment on macOS Mojave (10.14.x).

I am using MacPorts to manage the arm-none-eabi-* cross-compilation tools.
The GDB ARM cross-debugger currently shipped by MacPorts is version 7.9.
I have also gone thorough the code-signing of gdb as required for macOS operation.

My question has to do with what constitutes a compatible GDB setup.
When I tried to run gdbgui (using the provided `gdbgui_0.13.1.1` macos binary) and specifying the debugger via `--gdb arm-none-eabi-gdb`, it will fail with
```
The underlying gdb process has been killed. This tab will no longer function as expected.
```

Is this a gdb version issue or something else?

Note:
I can get it to work if I install gdb with multiarch support, but the multiarch gdb in MacPorts does not come with simulator support, and I'd need to bring in QEMU to be able to run the ARM programs. In addition, I am not familiar with the gdb<->qemu link setup, so it is rather clunky. I'm currently having to do the following in gdb:
```
target remote |exec qemu-system-arm -M virt -gdb stdio -S -kernel .elf
```
Which works but leaves a QEMU console in the background, and has a tendency to die whenever I press Ctrl-C to debug the program.