Manually stop and continue LLDB breakpoints on Xcode 26.4+#184690
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This pull request updates the IOSCoreDeviceLauncher and LLDB classes to incorporate an Xcode dependency, allowing for version-specific behavior during the iOS device attachment process. Specifically, it introduces a condition to skip breakpoint initialization when the Xcode version is 26.4.0. Review feedback indicates that the version number 26.4.0 is likely a typo and suggests implementing a more robust version range check. Additionally, it is recommended to replace the force-unwrap operator on the global Xcode instance with safer null handling to avoid potential runtime crashes.
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| r"breakpoint set --func-regex '^NOTIFY_DEBUGGER_ABOUT_RX_PAGES$'", | ||
| ); | ||
| final Version? xcodeVersion = _xcode.currentVersion; | ||
| final bool useManualContinue = xcodeVersion != null && (xcodeVersion >= Version(26, 4, 0)); |
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since the tradeoff is slower, can we maybe add a tracking issue in the case where apple fixes the bug to ensure we can revert to the auto-continue when it is fixed
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I can file one after. I don't think it needs to be committed in the code since there's no clear TODO
okorohelijah
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| } | ||
| // If the last log was a proces stop log, check if it was caused by a breakpoint. | ||
| if (processStopLine != null) { | ||
| if (line.contains('stop reason = breakpoint')) { |
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instead of manual string matching, should we consider using a regex pattern for stop reason = breakpoint
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What benefit would regex give here? To match on inconsistent spacing?
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yup but also to avoid false positives in cases where there might be similar string
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| final bool useManualContinue = xcodeVersion != null && (xcodeVersion >= Version(26, 4, 0)); | ||
| final breakpointSetCommand = useManualContinue | ||
| ? r"breakpoint set --func-regex '^NOTIFY_DEBUGGER_ABOUT_RX_PAGES$'" | ||
| : r"breakpoint set --auto-continue true --func-regex '^NOTIFY_DEBUGGER_ABOUT_RX_PAGES$'"; |
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i may be missing something, but why is it changing behavior for earlier versions (pre-26.4)?
Before:
breakpoint set --func-regex '^NOTIFY_DEBUGGER_ABOUT_RX_PAGES$'
After:
breakpoint set --auto-continue true --func-regex '^NOTIFY_DEBUGGER_ABOUT_RX_PAGES$'
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flutter/flutter@a0924c7...05e0ae0 2026-04-08 [email protected] Fix Android engine flags defaulting to true for malformed values (flutter/flutter#184631) 2026-04-08 [email protected] Try one more again (flutter/flutter#184767) 2026-04-08 [email protected] Remove custom `analysis_options.yaml` from `imitation_game_flutter` (flutter/flutter#184717) 2026-04-08 [email protected] Add more error handling to unawaited callsites (flutter/flutter#184526) 2026-04-08 [email protected] Refactor: remove material from absorb_ponter_test, container_test, lookup_boundary_test, page_view_test, router_test, semantics_clipping_test, semantics_merge_test, shadow_test, text_test (flutter/flutter#183309) 2026-04-08 [email protected] Remove editable_text_utils cross-imports from material and cupertino … (flutter/flutter#184519) 2026-04-08 [email protected] Replace hard coded max path length with system defined one. (flutter/flutter#184697) 2026-04-08 [email protected] [Re-land] Add Support For Built-in Kotlin (flutter/flutter#184745) 2026-04-08 [email protected] Manually stop and continue LLDB breakpoints on Xcode 26.4+ (flutter/flutter#184690) 2026-04-08 [email protected] Code freeze workflow (flutter/flutter#184246) 2026-04-08 [email protected] [Dot shorthands] Migrate examples/api/lib/widgets (flutter/flutter#183965) 2026-04-08 [email protected] [cupertino.dart] Implement CupertinoMenuAnchor and CupertinoMenuItem using RawMenuAnchor (flutter/flutter#182036) 2026-04-08 [email protected] [Semantics] clarify Android header docs (flutter/flutter#183573) 2026-04-08 [email protected] [ci] mac build_test bringup false (flutter/flutter#184738) 2026-04-08 [email protected] Reland "Apply rect clipping to surface views" (flutter/flutter#184732) 2026-04-08 [email protected] Remove bringup label for resharded Windows tool_integration_tests shards (flutter/flutter#184721) 2026-04-08 [email protected] Tool: Add search and filtering to widget preview scaffold (flutter/flutter#184023) 2026-04-08 [email protected] Update localization from translation console (flutter/flutter#184742) 2026-04-07 [email protected] Revert "Add Support For Built-in Kotlin (#184227)" (flutter/flutter#184739) 2026-04-07 [email protected] Collect HCPP adoption analytics for flutter run/build apk/build appbundle (flutter/flutter#184225) 2026-04-07 [email protected] Add a github workflow for reverting PRs. (flutter/flutter#184593) 2026-04-07 [email protected] Add Support For Built-in Kotlin (flutter/flutter#184227) 2026-04-07 [email protected] Revert "Apply rect clipping to surface views (#184471)" (flutter/flutter#184728) 2026-04-07 [email protected] [Fix-forward] Added Compose plugin to Add-to-app Integration Test (flutter/flutter#184681) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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…#184254) Xcode 26.4's LLDB has a race condition where breakpoints randomly fail to rearm after firing, causing EXC_BAD_ACCESS crashes on DartWorker threads (~80% failure rate). This disables LLDB's async mode via SetAsync(False) so breakpoint events are processed sequentially, eliminating the race. This re-lands the approach from flutter#184768 (reverted in flutter#184868 due to test failures) with corrected tests that expect synchronous mode output ('location added to breakpoint' instead of 'Process X resuming'). Also removes the manual stop/continue workaround from flutter#184690 and the Xcode version dependency from the LLDB class, since SetAsync(False) is safe on all LLDB versions. Upstream bug: llvm/llvm-project#190956
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…84690) When using LLDB to debug on a physical iOS device, we use LLDB breakpoints for JIT. However, it appears that LLDB fails to stop at the breakpoint sometimes. To workaround this, when using Xcode 26.4+, we don't use the LLDB auto-continue feature and instead wait for it to stop and restart it manually using the `continue` command. Fixes flutter#184254. ## Pre-launch Checklist - [x] I read the [Contributor Guide] and followed the process outlined there for submitting PRs. - [x] I read the [AI contribution guidelines] and understand my responsibilities, or I am not using AI tools. - [x] I read the [Tree Hygiene] wiki page, which explains my responsibilities. - [x] I read and followed the [Flutter Style Guide], including [Features we expect every widget to implement]. - [x] I signed the [CLA]. - [x] I listed at least one issue that this PR fixes in the description above. - [x] I updated/added relevant documentation (doc comments with `///`). - [x] I added new tests to check the change I am making, or this PR is [test-exempt]. - [x] I followed the [breaking change policy] and added [Data Driven Fixes] where supported. - [x] All existing and new tests are passing. If you need help, consider asking for advice on the #hackers-new channel on [Discord]. **Note**: The Flutter team is currently trialing the use of [Gemini Code Assist for GitHub](https://developers.google.com/gemini-code-assist/docs/review-github-code). Comments from the `gemini-code-assist` bot should not be taken as authoritative feedback from the Flutter team. If you find its comments useful you can update your code accordingly, but if you are unsure or disagree with the feedback, please feel free to wait for a Flutter team member's review for guidance on which automated comments should be addressed. <!-- Links --> [Contributor Guide]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview [AI contribution guidelines]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#ai-contribution-guidelines [Tree Hygiene]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md [test-exempt]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests [Flutter Style Guide]: https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md [Features we expect every widget to implement]: https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement [CLA]: https://cla.developers.google.com/ [flutter/tests]: https://github.com/flutter/tests [breaking change policy]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes [Discord]: https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md [Data Driven Fixes]: https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md
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When using LLDB to debug on a physical iOS device, we use LLDB breakpoints for JIT. However, it appears that LLDB fails to stop at the breakpoint sometimes. To workaround this, when using Xcode 26.4+, we don't use the LLDB auto-continue feature and instead wait for it to stop and restart it manually using the
continuecommand.Fixes #184254.
Pre-launch Checklist
///).If you need help, consider asking for advice on the #hackers-new channel on Discord.
Note: The Flutter team is currently trialing the use of Gemini Code Assist for GitHub. Comments from the
gemini-code-assistbot should not be taken as authoritative feedback from the Flutter team. If you find its comments useful you can update your code accordingly, but if you are unsure or disagree with the feedback, please feel free to wait for a Flutter team member's review for guidance on which automated comments should be addressed.