SUMMARY When I run KDevelop's tests or `kdevelop --help` or `kdevelop --rm <session name>`, the following lines appear at the very end of the program output: kdevplatform.language: Unregistering type class 57 kdevplatform.language: Unregistering type class 58 kdevplatform.language: Unregistering type class 39 kdevplatform.language: Unregistering type class 9 kdevplatform.language: Unregistering type class 20 kdevplatform.language: Unregistering type class 14 kdevplatform.language: Unregistering type class 21 kdevplatform.language: Unregistering type class 7 kdevplatform.language: Unregistering type class 8 kdevplatform.language: Unregistering type class 4 kdevplatform.language: Unregistering type class 3 kdevplatform.language: Unregistering type class 6 kdevplatform.language: Unregistering type class 5 kdevplatform.language: Unregistering type class 2 Sometimes it's just "Unregistering type class N" without the "kdevplatform.language: " prefix. The output is produced by the `qCDebug(LANGUAGE) << "Unregistering type class" << identity;` line in TypeSystem::unregisterTypeClassInternal() (https://invent.kde.org/kdevelop/kdevelop/-/blob/51e724364061a0a64576531dd0314a89fc688b05/kdevplatform/language/duchain/types/typeregister.cpp#L95), despite the fact that the logging level of all KDevelop logging categories (including kdevplatform.language) is above *debug*. I think, the issue is that this function is called very late, when some QLoggingCategory-related objects are already destroyed or uninitialized. In other words, this could be something like static de-initialization order fiasco issue. SOFTWARE/OS VERSIONS Manjaro GNU/Linux, Xfce KDE Frameworks Version: 5.85.0 Qt Version: 5.15.2+kde+r222
I receive this output when using opening files: `kdevelop file.js`
A possibly relevant merge request was started @ https://invent.kde.org/kdevelop/kdevelop/-/merge_requests/487
Git commit 07c1748bf71a3b6b2f8182146672ddc7558a032c by Igor Kushnir. Committed on 15/09/2023 at 14:50. Pushed by igorkushnir into branch 'master'. Revert "types: Remove unfilterable debug output" TypeSystem::registerTypeClassInternal() is called in the constructor and TypeSystem::unregisterTypeClassInternal() - in the destructor of each global-variable object declared via the REGISTER_TYPE macro. registerTypeClassInternal() does not log any messages, therefore these global variables are constructed before the function-local static QLoggingCategory constant LANGUAGE. So the global variables are destroyed after LANGUAGE (in the reverse order of the completion of constructors). unregisterTypeClassInternal() attempts to log a message via qCDebug(LANGUAGE) when the function-local LANGUAGE is already destroyed. This is undefined behavior, which in practice causes the following two issues: 1. When KDevelop is started normally and kdevplatform.language.debug=true, the "Unregistering type class" messages lack the usual prefix "kdevplatform.language: ". 2. When KDevelop exits immediately without showing the UI (because of a command-line option such as --help or --list-sessions) and kdevplatform.language.debug=false (the default), the disabled debug messages clutter the program output (curiously, they do start with the "kdevplatform.language: " prefix). Log a matching "Registering type class" message via qCDebug(LANGUAGE) in registerTypeClassInternal() to complete the constructor of LANGUAGE before the constructors of global variables that use LANGUAGE in their destructors. This eliminates the undefined behavior and its two practical consequences. The reverted commit's message contains: This is printed before Qt categorized logging is properly set up and thus may be printed even though it's technically disabled via filters. I haven't encountered the referenced issue during my testing of this commit. Perhaps the implementation of Qt categorized logging has improved since then (2017) and is now reliably set up in time. If not and the original issue resurfaces, the qCDebug(LANGUAGE) line in registerTypeClassInternal() can be replaced with the line `LANGUAGE();`, which does not log anything but still initializes the function-local static QLoggingCategory constant. This reverts commit a5eac48a83fc6e443459e7e045b9230b011c537b. FIXED-IN: 5.13.231200 M +1 -0 kdevplatform/language/duchain/types/typeregister.cpp https://invent.kde.org/kdevelop/kdevelop/-/commit/07c1748bf71a3b6b2f8182146672ddc7558a032c