OK, I'll just be honest: I had no idea that's how people used rr. I saw demos some years ago and assumed one used it similarly to gdb but with rewind.
I think this is an awesome use case for rewind debugging, that I had never thought of, and look forward to hopefully seeing it run on AMD Ryzen processors in the future, since I've bought into that ecosystem too much to go back already.
"I saw demos some years ago and assumed one used it similarly to gdb but with rewind."
You can do reverse debugging in gdb.
Here's how:
Run: gdb --args /usr/bin/foo --bar baz
Type "start", then "record", then "continue"
Now can try a number of reverse-debugging commands, for example:
* reverse-stepi
* reverse-next
* etc
gdb's built-in recording doesn't scale. You can't record across system calls, thread context switches, etc, and it's about a 1000x slowdown during record and replay. (rr is more like 2x.) It is, unfortunately, an attractive nuisance, because a lot of people have tried it out and concluded that record-and-replay debugging is useless.
I think this is an awesome use case for rewind debugging, that I had never thought of, and look forward to hopefully seeing it run on AMD Ryzen processors in the future, since I've bought into that ecosystem too much to go back already.