Include panic() and std::terminate() info in Sentry crash reports

[edolstra]

Motivation

This includes panic messages and uncaught exception type/message in crash reports.

Context

Summary by CodeRabbit

• New Features
  • Crash diagnostics now capture panic messages and additional exception details, and annotate unexpected process terminations for richer crash reports.
• Tests
  • Expanded functional tests to cover the new crash scenarios and validate enhanced error-reporting behavior.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 6994ab35-5b1f-4d77-b25c-9f46d7457750

📥 Commits

Reviewing files that changed from the base of the PR and between 77ebf8f and 83df16d.

📒 Files selected for processing (1)

• src/libutil/error.cc

🚧 Files skipped from review as they are similar to previous changes (1)

• src/libutil/error.cc

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📝 Walkthrough

Walkthrough

Adds Sentry tagging for panic messages and uncaught termination exceptions, installs a terminate handler that tags exception type/message before termination, and extends crash tests to exercise panic and destructor-throw termination scenarios.

Changes

Sentry Crash Reporting

Layer / File(s)	Summary
Panic function Sentry reporting src/libutil/error.cc	Sentry header included; panic() sets panic_msg Sentry tag with the provided message before calling std::terminate().
Terminate exception handler installation src/nix/main.cc	Adds terminateHandler() that extracts current exception info, sets Sentry tags for type and message, and delegates to default termination. Installs handler via std::set_terminate() during Sentry initialization.
Crash test scenarios for panic and terminate src/nix/crash.cc, tests/functional/sentry.sh	Adds doThrow() helper and panic/terminate crash modes to CmdCrash; updates functional test loop to include the new crash types.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~45 minutes

Possibly related PRs

• DeterminateSystems/nix-src#436: Modifies src/nix/main.cc's Sentry initialization path and tag usage.
• DeterminateSystems/nix-src#433: Also touches mainWrapped startup/Sentry integration and related initialization flow.

Suggested reviewers

• cole-h

Poem

🐰 A hop, a tag, a careful trace,
I set the panic in its place.
When handlers catch what goes astray,
Sentry stores the words we say.
Hooray for logs that saved the day!

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: adding panic() and std::terminate() information to Sentry crash reports, which is reflected across all modified files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch more-sentry

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/libutil/error.cc`:
- Line 456: setSentryTag is being called with msg.data() where msg is a
std::string_view, but std::string_view::data() is not null-terminated; convert
the view to a null-terminated string before passing it to setSentryTag (e.g.,
construct a std::string from msg and pass its c_str()), or alternatively change
setSentryTag to accept a std::string_view and make an internal copy; update the
call site (setSentryTag("panic_msg", msg)) or the setSentryTag implementation so
the value associated with "panic_msg" is always a null-terminated buffer.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 17bb80ac-731c-41fa-b04a-e06c950a2cdd

📥 Commits

Reviewing files that changed from the base of the PR and between 5dbb952 and 77ebf8f.

📒 Files selected for processing (4)

• src/libutil/error.cc
• src/nix/crash.cc
• src/nix/main.cc
• tests/functional/sentry.sh

[github-actions]

🚀 Deployed on https://6a06e91f65e7183bfebf3bc1--determinate-nix.netlify.app