rr-debugger / rr-debugger/rr

Breakpoint on trap instruction isn't hit

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Dominant language
C++
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Description

The problem is that if the breakpoint target is already a trap instruction, gdb never asks rr to set the breakpoint. rr has logic to handle breakpoint-on-trap-instruction, but gdb doesn't allow that logic to kick in. And for some reason gdb doesn't know how to handle the notifications that rr sends it, which AFAICT follow spec.

I consider this to be something of a problem, but I don't think it's worth the time right now to figure out what dance gdb wants us to do.

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  3. Fork the repository and make your change on a branch.
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Research direction

Start by reproducing a breakpoint whose target is already a trap instruction, then inspect rr's existing breakpoint-on-trap-instruction logic and the notifications it sends to gdb. Determine the gdb interaction needed for rr to set and report the breakpoint; done means the breakpoint is hit and gdb handles the notifications correctly.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp, linux
Domain
devtools
Issue type
Bug
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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