It's worth noting that upstream gdb (and clang) are somewhat limited in GPU debugging support because they only use (and emit) standardized DWARF debug information. The DWARF standard will need updates before gdb and clang can reach parity with the AMD forks, rocgdb and amdclang, in terms of debugging support. It's nothing fundamental, but the AMD forks use experimental DWARF features and the upstream projects do not.
It's a little out of date now, but Lance Six had a presentation about the state of AMD GPU debugging in upstream gdb at FOSDEM 2024. https://archive.fosdem.org/2024/events/attachments/fosdem-20...