This PR seems to have changed how watchpoints are set and may be relevant here?
https://github.com/openocd-org/openocd/commit/fb43f1ff4e2f0638110ffcc4e63bee8b5361db64#diff-18b6c875f0bfee773f2a5e6e0a100e4d9c641fec9c870d4da22ca0aa957259c8L914 - watchpoint->set = wp_num + 1; + watchpoint->number = wp_num;
