"r <num>" and "r <string>" in coqtop Ltac debugger broken

[jfehrle]

Description of the problem

The r <num>and r <string> commands in the coqtop Ltac debugger generate action op failures. After fixing that immediate problem, these commands never cause the debugger to stop in another breakpoint, rendering them useless.

This breaks using the Ltac debugger through Proof General (relying on coqtop). I only learned about this recently when someone made a one line comment as an aside in one of our online media (I can't remember where) that the debugger in Proof General has been broken since 8.15. If someone had reported this earlier, it would have been fixed a long time ago.

Coq Version 8.15 to 8.18