rr-debugger / rr-debugger/rr

Assertion failure in rr while rr record --chaos.

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Dominant language
C++
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Description

I'm trying to run a binary that I'm afraid I can't post publicly and when I running:

rr record --chaos <private_bin>

I get the following crash:

[FATAL /home/andronat/rr/src/record_syscall.cc:5549:process_mmap()]
 (task 2177935 (rec:2177935) at time 1099)
 -> Assertion `rt->fd_table()->get_monitor(f.fd)->type() == FileMonitor::Type::Mmapped' failed to hold. Expected monitor type Mmapped for fd 100, got monitor type 3

Any ideas what is the problem and how can I fix it?

Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by examining src/record_syscall.cc around process_mmap() at line 5549 and reproduce the reported rr record --chaos <private_bin> invocation if possible. Trace why fd 100 has monitor type 3 instead of the expected Mmapped type; done means the assertion is understood and the reported recording scenario no longer crashes.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp, linux
Domain
devtools, operating-systems
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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