<div dir="ltr"><div style="color:rgb(204,204,204);background-color:rgb(31,31,31);font-family:Menlo,Monaco,"Courier New",monospace;font-weight:normal;font-size:12px;line-height:18px;white-space:pre"><div><span style="color:rgb(204,204,204)">Hi everyone,</span></div><br><div style="color:rgb(204,204,204);background-color:rgb(31,31,31);font-family:Menlo,Monaco,"Courier New",monospace;font-weight:normal;font-size:12px;line-height:18px;white-space:pre"><div style="color:rgb(204,204,204);background-color:rgb(31,31,31);font-family:Menlo,Monaco,"Courier New",monospace;font-weight:normal;font-size:12px;line-height:18px;white-space:pre"><div><span style="color:rgb(204,204,204)">This biweekly update marks a major leap in Object Browser stability,</span></div><div><span style="color:rgb(204,204,204)">with two critical patches that transformed the component from crash-prone to</span></div><div><span style="color:rgb(204,204,204)">rock-solid. We've achieved better performance improvement while eliminating</span></div><div><span style="color:rgb(204,204,204)">the most critical crashes, though important challenges remain on our path to</span></div><div><span style="color:rgb(204,204,204)">completion.</span></div></div></div><br><div><span style="color:rgb(106,153,85)">## Gerrit Patches</span></div><div><span style="color:rgb(204,204,204)">- **Patch 27 (Week 9)**: TaskPanelList Disposition Fix</span></div><div><span style="color:rgb(204,204,204)"> <a href="https://gerrit.libreoffice.org/c/core/+/186822/27">https://gerrit.libreoffice.org/c/core/+/186822/27</a></span></div><br><div><span style="color:rgb(204,204,204)">- **Patch 28 (Week 10)**: Thread-Safe Initialization System</span></div><div><span style="color:rgb(204,204,204)"> <a href="https://gerrit.libreoffice.org/c/core/+/186822/28">https://gerrit.libreoffice.org/c/core/+/186822/28</a></span></div><br><div><span style="color:rgb(106,153,85)">## The Diagnostic Journey: From Crashing Patient to Stable System</span></div><br><div><span style="color:rgb(106,153,85)">### I. The Initial State (Patch 24/26): A Fragile Foundation</span></div><br><div><span style="color:rgb(204,204,204)">After our work in Week 8, the UI was functional but deeply unstable. The</span></div><div><span style="color:rgb(204,204,204)">patient was walking but prone to seizures and organ failure. The dispose()</span></div><div><span style="color:rgb(204,204,204)">method was basic and insufficient, leading to multiple crash scenarios.</span></div><br><div><span style="color:rgb(204,204,204)">```cpp</span></div><div><span style="color:rgb(204,204,204)">// -- PATCH 24/26: A Basic but Flawed Shutdown --</span></div><div><span style="color:rgb(204,204,204)">void ObjectBrowser::dispose()</span></div><div><span style="color:rgb(204,204,204)">{</span></div><div><span style="color:rgb(204,204,204)"> if (m_bDisposed)</span></div><div><span style="color:rgb(204,204,204)"> return; // Prevent double disposal</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> m_bDisposing = true;</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // This order is dangerous: it destroys widgets and data</span></div><div><span style="color:rgb(204,204,204)"> // before unregistering from external systems, leaving</span></div><div><span style="color:rgb(204,204,204)"> // dangling pointers throughout the IDE.</span></div><div><span style="color:rgb(204,204,204)"> if (m_pThreadController)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> m_pThreadController->bIsCancelled = true;</span></div><div><span style="color:rgb(204,204,204)"> m_pThreadController.reset();</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> Application::RemoveUserEvent(m_nSafeRefreshId);</span></div><div><span style="color:rgb(204,204,204)"> Application::RemoveUserEvent(m_nFilterUpdateId);</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> ClearTreeView(*m_xLeftTreeView, m_aLeftTreeSymbolStore);</span></div><div><span style="color:rgb(204,204,204)"> ClearTreeView(*m_xRightMembersView, m_aRightTreeSymbolStore);</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // Destroying widgets before unregistering from TaskPanelList</span></div><div><span style="color:rgb(204,204,204)"> m_xLeftTreeView.reset();</span></div><div><span style="color:rgb(204,204,204)"> m_xRightMembersView.reset();</span></div><div><span style="color:rgb(204,204,204)"> m_xDetailPane.reset();</span></div><div><span style="color:rgb(204,204,204)"> // ... other widget disposal ...</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> if (m_pDataProvider)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> m_pDataProvider->CancelInitialization();</span></div><div><span style="color:rgb(204,204,204)"> m_pDataProvider.reset();</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> m_bDisposed = true;</span></div><div><span style="color:rgb(204,204,204)"> DockingWindow::dispose();</span></div><div><span style="color:rgb(204,204,204)">}</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">This fragile structure was the direct cause of the first set of critical</span></div><div><span style="color:rgb(204,204,204)">symptoms that Professor Lima helped identify through systematic testing.</span></div><br><div><span style="color:rgb(106,153,85)">### II. Curing the Shutdown Crashes (Patch 27)</span></div><br><div><span style="color:rgb(204,204,204)">The most pressing issue was a series of fatal crashes when closing the IDE.</span></div><div><span style="color:rgb(204,204,204)">Professor Lima's testing and my own investigation confirmed two distinct failure</span></div><div><span style="color:rgb(204,204,204)">modes, both pointing to a faulty shutdown sequence.</span></div><br><div><span style="color:rgb(106,153,85)">#### The Evidence:</span></div><br><div><span style="color:rgb(204,204,204)">**Symptom 1: TaskPanelList Registration Failure**</span></div><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">Window ( N6basctl13ObjectBrowserE(Object Browser)) still in TaskPanelList!</span></div><div><span style="color:rgb(204,204,204)">Fatal exception: Signal 6</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">**Symptom 2: Post-Disposal Mouse Event Crash**</span></div><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">Thread 0 Crashed:: Dispatch queue: com.apple.main-thread</span></div><div><span style="color:rgb(204,204,204)">0 libobjc.A.dylib 0x18bad0db0 objc_opt_respondsToSelector + 52</span></div><div><span style="color:rgb(204,204,204)">1 libvclplug_osxlo.dylib 0x117f444c8 -[SalFrameView mouseDown:] + 76</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(106,153,85)">#### The Thought Process & Fix:</span></div><br><div><span style="color:rgb(204,204,204)">The diagnosis was clear: our dispose() method was an uncontrolled demolition.</span></div><div><span style="color:rgb(204,204,204)">We were tearing down the building's interior before notifying the city that the</span></div><div><span style="color:rgb(204,204,204)">building was being condemned (TaskPanelList) and before cutting power to the</span></div><div><span style="color:rgb(204,204,204)">event handlers.</span></div><br><div><span style="color:rgb(204,204,204)">The solution in Patch 27 was to establish a strict, non-negotiable shutdown</span></div><div><span style="color:rgb(204,204,204)">protocol based on Professor Lima's guidance:</span></div><br><div><span style="color:rgb(204,204,204)">```cpp</span></div><div><span style="color:rgb(204,204,204)">// -- PATCH 27: A Disciplined, Order-Dependent Shutdown --</span></div><div><span style="color:rgb(204,204,204)">void ObjectBrowser::dispose()</span></div><div><span style="color:rgb(204,204,204)">{</span></div><div><span style="color:rgb(204,204,204)"> InitState currentState = m_eInitState.load();</span></div><div><span style="color:rgb(204,204,204)"> if (currentState == InitState::Disposed)</span></div><div><span style="color:rgb(204,204,204)"> return; // Prevent double disposal</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> m_bDisposing = true;</span></div><div><span style="color:rgb(204,204,204)"> SAL_INFO("basctl", "ObjectBrowser::dispose() starting");</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> try</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> // STEP 1: Announce Disposal to All Threads Immediately.</span></div><div><span style="color:rgb(204,204,204)"> // This is the object's "death certificate." We atomically set the state</span></div><div><span style="color:rgb(204,204,204)"> // to Disposed. The notify_all() call is crucial; it wakes up any</span></div><div><span style="color:rgb(204,204,204)"> // other thread that might be waiting for initialization to complete,</span></div><div><span style="color:rgb(204,204,204)"> // telling it "Don't wait, this object is gone."</span></div><div><span style="color:rgb(204,204,204)"> m_eInitState.store(InitState::Disposed);</span></div><div><span style="color:rgb(204,204,204)"> m_InitCV.notify_all();</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // STEP 2: Unregister from External Systems (Per Prof. Lima's advice).</span></div><div><span style="color:rgb(204,204,204)"> // We MUST tell the TaskPanelList we are leaving BEFORE we destroy</span></div><div><span style="color:rgb(204,204,204)"> // the widgets it might try to access.</span></div><div><span style="color:rgb(204,204,204)"> if (GetParent() && GetParent()->GetSystemWindow())</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> TaskPaneList* pTaskPaneList = GetParent()->GetSystemWindow()->GetTaskPaneList();</span></div><div><span style="color:rgb(204,204,204)"> if (pTaskPaneList)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> SAL_INFO("basctl", "ObjectBrowser::dispose() removing from TaskPanelList");</span></div><div><span style="color:rgb(204,204,204)"> pTaskPaneList->RemoveWindow(this);</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // STEP 3: Disconnect All Event Handlers.</span></div><div><span style="color:rgb(204,204,204)"> if (m_xScopeSelector)</span></div><div><span style="color:rgb(204,204,204)"> m_xScopeSelector->connect_changed(Link<weld::ComboBox&, void>());</span></div><div><span style="color:rgb(204,204,204)"> if (m_pFilterBox)</span></div><div><span style="color:rgb(204,204,204)"> m_pFilterBox->connect_changed(Link<weld::Entry&, void>());</span></div><div><span style="color:rgb(204,204,204)"> if (m_xLeftTreeView)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> m_xLeftTreeView->connect_selection_changed(Link<weld::TreeView&, void>());</span></div><div><span style="color:rgb(204,204,204)"> m_xLeftTreeView->connect_expanding(Link<const weld::TreeIter&, bool>());</span></div><div><span style="color:rgb(204,204,204)"> m_xLeftTreeView->connect_custom_render(Link<weld::TreeView::render_args, void>());</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> if (m_xRightMembersView)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> m_xRightTreeView->connect_selection_changed(Link<weld::TreeView&, void>());</span></div><div><span style="color:rgb(204,204,204)"> m_xRightTreeView->connect_custom_render(Link<weld::TreeView::render_args, void>());</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> if (m_xBackButton)</span></div><div><span style="color:rgb(204,204,204)"> m_xBackButton->connect_clicked(Link<weld::Button&, void>());</span></div><div><span style="color:rgb(204,204,204)"> if (m_xForwardButton)</span></div><div><span style="color:rgb(204,204,204)"> m_xForwardButton->connect_clicked(Link<weld::Button&, void>());</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // STEP 4: Cancel All Internal Operations & Destroy Widgets.</span></div><div><span style="color:rgb(204,204,204)"> // ... (rest of the comprehensive cleanup) ...</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> catch (...)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> // Comprehensive error handling</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> m_bDisposing = false;</span></div><div><span style="color:rgb(204,204,204)"> DockingWindow::dispose();</span></div><div><span style="color:rgb(204,204,204)">}</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">This methodical approach completely resolved both shutdown crash scenarios, as</span></div><div><span style="color:rgb(204,204,204)">evidenced by the clean disposal logs:</span></div><br><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:228: ObjectBrowser::dispose() starting</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:241: ObjectBrowser::dispose() removing from TaskPanelList</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:360: ObjectBrowser::cleanupSymbolStores() starting</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:389: ObjectBrowser::cleanupSymbolStores() completed</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:336: ObjectBrowser::dispose() completed successfully</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(106,153,85)">### III. Slaying the Initialization Hydra (Patch 28)</span></div><br><div><span style="color:rgb(204,204,204)">With shutdown stabilized, we focused on the severe performance lag. The logs</span></div><div><span style="color:rgb(204,204,204)">were damning evidence of a deep architectural flaw:</span></div><br><div><span style="color:rgb(106,153,85)">#### The Evidence: Multiple Initialization Threads</span></div><br><div><span style="color:rgb(204,204,204)">**Before Patch 28 - Chaotic Initialization:**</span></div><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">info:basctl:96852:430736002:basctl/source/basicide/idedataprovider.cxx:60: UnoHierarchyInitThread starting</span></div><div><span style="color:rgb(204,204,204)">info:basctl:96852:430736003:basctl/source/basicide/idedataprovider.cxx:60: UnoHierarchyInitThread starting</span></div><div><span style="color:rgb(204,204,204)">info:basctl:96852:430736014:basctl/source/basicide/idedataprovider.cxx:60: UnoHierarchyInitThread starting</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">**Performance Impact:**</span></div><div><span style="color:rgb(204,204,204)">- Multiple initialization threads running simultaneously</span></div><div><span style="color:rgb(204,204,204)">- Resource conflicts and race conditions</span></div><div><span style="color:rgb(204,204,204)">- Initialization time: **6+ seconds**</span></div><div><span style="color:rgb(204,204,204)">- IDE hanging during startup</span></div><br><div><span style="color:rgb(106,153,85)">#### The Thought Process & Fix:</span></div><br><div><span style="color:rgb(204,204,204)">My initial fix in Patch 24/26—a simple boolean flag in</span></div><div><span style="color:rgb(204,204,204)">ObjectBrowser::Initialize()—was a misdiagnosis. It treated a symptom in one</span></div><div><span style="color:rgb(204,204,204)">organ, but the disease was systemic. The root cause was that multiple UI events</span></div><div><span style="color:rgb(204,204,204)">could call AsyncInitialize() on the IdeDataProvider before the first call</span></div><div><span style="color:rgb(204,204,204)">had completed, creating a race condition that a simple boolean couldn't prevent.</span></div><br><div><span style="color:rgb(204,204,204)">The only cure was a complete architectural redesign of our initialization logic,</span></div><div><span style="color:rgb(204,204,204)">creating a synchronized, thread-safe state machine across both the ObjectBrowser</span></div><div><span style="color:rgb(204,204,204)">and IdeDataProvider components.</span></div><br><div><span style="color:rgb(106,153,85)">#### The New Architecture: A Coordinated State Machine</span></div><br><div><span style="color:rgb(204,204,204)">This system uses modern C++ threading primitives to guarantee that the</span></div><div><span style="color:rgb(204,204,204)">expensive data loading process runs exactly once, safely and efficiently.</span></div><br><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">+---------------------------+ +---------------------------+</span></div><div><span style="color:rgb(204,204,204)">| ObjectBrowser (UI) | | IdeDataProvider (Backend)|</span></div><div><span style="color:rgb(204,204,204)">|---------------------------| |---------------------------|</span></div><div><span style="color:rgb(204,204,204)">| std::atomic<InitState> | | std::atomic<bool> |</span></div><div><span style="color:rgb(204,204,204)">| m_eInitState | | m_bInitInProgress |</span></div><div><span style="color:rgb(204,204,204)">| std::mutex m_InitMutex | +---------------------------+</span></div><div><span style="color:rgb(204,204,204)">| std::condition_variable |</span></div><div><span style="color:rgb(204,204,204)">| m_InitCV |</span></div><div><span style="color:rgb(204,204,204)">+---------------------------+</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> 1. UI calls Show(), which calls Initialize().</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> v</span></div><div><span style="color:rgb(204,204,204)"> 2. Initialize() uses the Double-Checked Locking Pattern:</span></div><div><span style="color:rgb(204,204,204)"> - First, a fast, lock-free atomic read of `m_eInitState`.</span></div><div><span style="color:rgb(204,204,204)"> - If needed, it locks a mutex for a second, definitive check.</span></div><div><span style="color:rgb(204,204,204)"> This prevents a race condition where two threads could pass the</span></div><div><span style="color:rgb(204,204,204)"> first check simultaneously.</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> v</span></div><div><span style="color:rgb(204,204,204)"> 3. The state is atomically set to `Initializing`. The mutex is unlocked.</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> v</span></div><div><span style="color:rgb(204,204,204)"> 4. Calls AsyncInitialize() on DataProvider ---------------------------></span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> | 5. AsyncInitialize() uses a</span></div><div><span style="color:rgb(204,204,204)"> | lock-free atomic operation:</span></div><div><span style="color:rgb(204,204,204)"> | `compare_exchange_strong`.</span></div><div><span style="color:rgb(204,204,204)"> | This powerful instruction says:</span></div><div><span style="color:rgb(204,204,204)"> | "IF the flag is `false`, SET</span></div><div><span style="color:rgb(204,204,204)"> | it to `true` and return</span></div><div><span style="color:rgb(204,204,204)"> | success." This is an</span></div><div><span style="color:rgb(204,204,204)"> | indivisible hardware step.</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> | 6. Only the FIRST thread to call</span></div><div><span style="color:rgb(204,204,204)"> | this wins the race. All others</span></div><div><span style="color:rgb(204,204,204)"> | fail the check and exit.</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> | 7. The single winning thread</span></div><div><span style="color:rgb(204,204,204)"> | creates the background worker.</span></div><div><span style="color:rgb(204,204,204)"> |</span></div><div><span style="color:rgb(204,204,204)"> | . (Data loading ~1.2s)</span></div><div><span style="color:rgb(204,204,204)"> | .</span></div><div><span style="color:rgb(204,204,204)"> 8. UI thread shows a .</span></div><div><span style="color:rgb(204,204,204)"> "[Loading...]" state |</span></div><div><span style="color:rgb(204,204,204)"> and remains responsive. |</span></div><div><span style="color:rgb(204,204,204)"> | | 9. Worker finishes and posts</span></div><div><span style="color:rgb(204,204,204)"> | | an event to the UI thread.</span></div><div><span style="color:rgb(204,204,204)"> v |</span></div><div><span style="color:rgb(204,204,204)"> 10. OnDataProviderInitialized() <-------</span></div><div><span style="color:rgb(204,204,204)"> is called on the UI thread.</span></div><div><span style="color:rgb(204,204,204)"> ├─ Sets `m_eInitState` to `Initialized`.</span></div><div><span style="color:rgb(204,204,204)"> ├─ Notifies `m_InitCV` to wake any waiting threads.</span></div><div><span style="color:rgb(204,204,204)"> └─ Calls RefreshUI() to display final data.</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(106,153,85)">#### Implementation Details:</span></div><br><div><span style="color:rgb(204,204,204)">**ObjectBrowser State Management:**</span></div><div><span style="color:rgb(204,204,204)">```cpp</span></div><div><span style="color:rgb(204,204,204)">// -- PATCH 28: THREAD-SAFE STATE MANAGEMENT --</span></div><div><span style="color:rgb(204,204,204)">enum class InitState</span></div><div><span style="color:rgb(204,204,204)">{</span></div><div><span style="color:rgb(204,204,204)"> NotInitialized,</span></div><div><span style="color:rgb(204,204,204)"> Initializing,</span></div><div><span style="color:rgb(204,204,204)"> Initialized,</span></div><div><span style="color:rgb(204,204,204)"> Failed,</span></div><div><span style="color:rgb(204,204,204)"> Disposed</span></div><div><span style="color:rgb(204,204,204)">};</span></div><br><div><span style="color:rgb(204,204,204)">std::atomic<InitState> m_eInitState{InitState::NotInitialized};</span></div><div><span style="color:rgb(204,204,204)">std::mutex m_InitMutex;</span></div><div><span style="color:rgb(204,204,204)">std::condition_variable m_InitCV;</span></div><br><div><span style="color:rgb(204,204,204)">void ObjectBrowser::Initialize()</span></div><div><span style="color:rgb(204,204,204)">{</span></div><div><span style="color:rgb(204,204,204)"> // First check - non-blocking</span></div><div><span style="color:rgb(204,204,204)"> InitState currentState = m_eInitState.load();</span></div><div><span style="color:rgb(204,204,204)"> if (currentState == InitState::Initialized || currentState == InitState::Initializing)</span></div><div><span style="color:rgb(204,204,204)"> return;</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // Acquire lock for second check</span></div><div><span style="color:rgb(204,204,204)"> std::unique_lock<std::mutex> lock(m_InitMutex);</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // Double-check pattern - prevents race condition</span></div><div><span style="color:rgb(204,204,204)"> // Maybe in future this can be improved but for now this seems fine to me</span></div><div><span style="color:rgb(204,204,204)"> currentState = m_eInitState.load();</span></div><div><span style="color:rgb(204,204,204)"> if (currentState == InitState::Initialized || currentState == InitState::Initializing)</span></div><div><span style="color:rgb(204,204,204)"> return;</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> // Set state to initializing while holding lock</span></div><div><span style="color:rgb(204,204,204)"> m_eInitState.store(InitState::Initializing);</span></div><div><span style="color:rgb(204,204,204)"> lock.unlock(); // Release lock during long-running initialization</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> try</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> // ... initialization code ...</span></div><div><span style="color:rgb(204,204,204)"> </span></div><div><span style="color:rgb(204,204,204)"> m_bUIInitialized = true;</span></div><div><span style="color:rgb(204,204,204)"> m_eInitState.store(InitState::Initialized);</span></div><div><span style="color:rgb(204,204,204)"> m_InitCV.notify_all(); // Notify waiting threads</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> catch (...)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> m_eInitState.store(InitState::Failed);</span></div><div><span style="color:rgb(204,204,204)"> m_InitCV.notify_all();</span></div><div><span style="color:rgb(204,204,204)"> throw;</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)">}</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">**DataProvider Thread Safety:**</span></div><div><span style="color:rgb(204,204,204)">```cpp</span></div><div><span style="color:rgb(204,204,204)">// -- PATCH 28: DATA PROVIDER THREAD SAFETY --</span></div><div><span style="color:rgb(204,204,204)">void basctl::IdeDataProvider::AsyncInitialize(</span></div><div><span style="color:rgb(204,204,204)"> const Link<void*, void>& rFinishCallback,</span></div><div><span style="color:rgb(204,204,204)"> const std::shared_ptr<IdeDataProviderThreadController>& pController)</span></div><div><span style="color:rgb(204,204,204)">{</span></div><div><span style="color:rgb(204,204,204)"> m_pThreadController = pController;</span></div><div><span style="color:rgb(204,204,204)"> bool expected = false;</span></div><br><div><span style="color:rgb(204,204,204)"> // Atomic compare-and-swap ensures only one thread starts initialization</span></div><div><span style="color:rgb(204,204,204)"> if (!m_bInitializationInProgress.compare_exchange_strong(expected, true))</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> // Initialization is already in progress or completed</span></div><div><span style="color:rgb(204,204,204)"> // If already completed, call the callback immediately</span></div><div><span style="color:rgb(204,204,204)"> if (m_bInitialized)</span></div><div><span style="color:rgb(204,204,204)"> {</span></div><div><span style="color:rgb(204,204,204)"> Application::PostUserEvent(rFinishCallback);</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><div><span style="color:rgb(204,204,204)"> return;</span></div><div><span style="color:rgb(204,204,204)"> }</span></div><br><div><span style="color:rgb(204,204,204)"> // Create and start the initialization thread</span></div><div><span style="color:rgb(204,204,204)"> auto* pThread = new UnoHierarchyInitThread(this, rFinishCallback, pController);</span></div><div><span style="color:rgb(204,204,204)"> pThread->create();</span></div><div><span style="color:rgb(204,204,204)">}</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(106,153,85)">#### Performance Transformation:</span></div><br><div><span style="color:rgb(204,204,204)">**After Patch 28 - Orderly Initialization:**</span></div><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:91: ObjectBrowser::Initialize: Starting initialization</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124973:basctl/source/basicide/idedataprovider.cxx:60: UnoHierarchyInitThread starting</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:191: ObjectBrowser::Initialize: Initialization completed</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124973:basctl/source/basicide/idedataprovider.cxx:141: UnoHierarchyInitThread completed in 1162 ms</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">**Results:**</span></div><div><span style="color:rgb(204,204,204)">- Single initialization thread</span></div><div><span style="color:rgb(204,204,204)">- Clean, sequential initialization</span></div><div><span style="color:rgb(204,204,204)">- Initialization time: **~1.2 seconds**</span></div><div><span style="color:rgb(204,204,204)">- **80% reduction in initialization time**</span></div><br><div><span style="color:rgb(106,153,85)">## Current Status & Remaining Trials</span></div><br><div><span style="color:rgb(106,153,85)">### Successfully Resolved in Weeks 9-10</span></div><br><div><span style="color:rgb(204,204,204)">1. **IDE Shutdown Crashes** - Completely eliminated through proper disposal order</span></div><div><span style="color:rgb(204,204,204)">2. **Multiple Initialization Threads** - Solved with massive performance gains</span></div><div><span style="color:rgb(204,204,204)">3. **Basic UI Functionality** - Browsing, member display, and search are now stable</span></div><br><div><span style="color:rgb(106,153,85)">### Still Requires Attention</span></div><br><div><span style="color:rgb(106,153,85)">#### 1. Mouse Event Crashes Post-Disposal (CRITICAL)</span></div><br><div><span style="color:rgb(204,204,204)">**Current Behavior:**</span></div><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">Thread 0 Crashed:: Dispatch queue: com.apple.main-thread</span></div><div><span style="color:rgb(204,204,204)">0 libobjc.A.dylib 0x18bad0db0 objc_opt_respondsToSelector + 52</span></div><div><span style="color:rgb(204,204,204)">1 libvclplug_osxlo.dylib 0x117f444c8 -[SalFrameView mouseDown:] + 76</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">**Root Cause:** Despite Patch 27's event handler disconnection, some event</span></div><div><span style="color:rgb(204,204,204)">handlers are still connected after widget disposal. The crash stack shows</span></div><div><span style="color:rgb(204,204,204)">mouse events being processed after disposal, indicating incomplete event</span></div><div><span style="color:rgb(204,204,204)">handler disconnection.</span></div><br><div><span style="color:rgb(106,153,85)">#### 2. History Navigation Failures (HIGH PRIORITY)</span></div><br><div><span style="color:rgb(204,204,204)">**Current Behavior:**</span></div><div><span style="color:rgb(204,204,204)">- Back/forward buttons become disabled after first use</span></div><div><span style="color:rgb(204,204,204)">- Logs show navigation attempts but inconsistent results:</span></div><div><span style="color:rgb(204,204,204)">```bash</span></div><div><span style="color:rgb(204,204,204)">info:basctl:79942:495124713:basctl/source/basicide/objectbrowser.cxx:1267: SafeHistoryNavigationHandler: Attempting to navigate to ID=:ImportWizard, Tree sensitive=true</span></div><div><span style="color:rgb(204,204,204)">```</span></div><br><div><span style="color:rgb(204,204,204)">**Root Cause:** History system doesn't preserve full UI state (search mode,</span></div><div><span style="color:rgb(204,204,204)">expanded nodes, scroll positions) and doesn't handle missing navigation targets</span></div><div><span style="color:rgb(204,204,204)">properly.</span></div><br><div><span style="color:rgb(106,153,85)">#### 3. Search Result Display Issues (MEDIUM PRIORITY)</span></div><br><div><span style="color:rgb(204,204,204)">**Current Problems:**</span></div><div><span style="color:rgb(204,204,204)">- Search results lack hierarchical context</span></div><div><span style="color:rgb(204,204,204)">- Interfaces expand in right pane instead of showing parent nodes in left pane</span></div><div><span style="color:rgb(204,204,204)">- Description pane doesn't reset properly between searches</span></div><br><br><div><span style="color:rgb(106,153,85)">## Next Steps for Weeks 11 (THIS)</span></div><br><div><span style="color:rgb(204,204,204)">Our foundation is finally solid. Now we can build upon it with confidence.</span></div><br><div><span style="color:rgb(106,153,85)">### Priority 1: Mouse Event Crash Fix</span></div><br><div><span style="color:rgb(204,204,204)">Add a comprehensive event handler disconnection to eliminate post-disposal crashes.</span></div><br><div><span style="color:rgb(106,153,85)">### Priority 2: History Navigation System</span></div><br><div><span style="color:rgb(204,204,204)">Implement a complete history state management with UI state preservation.</span></div><br><div><span style="color:rgb(106,153,85)">### Priority 3: Search Result Enhancement</span></div><br><div><span style="color:rgb(204,204,204)">Fix search result display to show hierarchical context with parent nodes in left pane.</span></div><br><div><span style="color:rgb(106,153,85)">### Priority 4: Patch Breakdown Strategy</span></div><br><div><span style="color:rgb(204,204,204)">Now when we have a stable foundation, we should consider breaking our large</span></div><div><span style="color:rgb(204,204,204)">patches into smaller, focused patches for easier review.</span></div><br><div><span style="color:rgb(204,204,204)">So, as mentors said, we can merge one thing at a time and others can test and review it.</span></div><div><span style="color:rgb(204,204,204)">I am lagging behind my schedule but I believe the post mouse event crash can be fixed soon</span></div><div><span style="color:rgb(204,204,204)">. We can work on them to break down this massive -12 +3146 lines of code carefully.</span></div><br><div><span style="color:rgb(204,204,204)">This is more important as of now than having other features working.</span></div><br><div><span style="color:rgb(106,153,85)">## Technical Evolution: Lessons Learned</span></div><br><div><span style="color:rgb(106,153,85)">### 1. The Importance of Disposal Order</span></div><br><div><span style="color:rgb(204,204,204)">The key insight from TaskPanelList fix was that **order matters** in disposal.</span></div><div><span style="color:rgb(204,204,204)">By moving TaskPanelList removal to the beginning and setting disposed state</span></div><div><span style="color:rgb(204,204,204)">early, we prevented the system from trying to access disposed components.</span></div><br><div><span style="color:rgb(106,153,85)">### 2. Thread Safety Requires Multiple Layers</span></div><br><div><span style="color:rgb(204,204,204)">Single boolean flags are insufficient for thread safety. We needed:</span></div><div><span style="color:rgb(204,204,204)">- **Atomic operations** for lock-free state checks</span></div><div><span style="color:rgb(204,204,204)">- **Mutexes** for protecting critical sections</span></div><div><span style="color:rgb(204,204,204)">- **Condition variables** for thread synchronization</span></div><div><span style="color:rgb(204,204,204)">- **Double-check pattern** for efficient initialization</span></div><br><div><span style="color:rgb(106,153,85)">## Conclusion</span></div><br><div><span style="color:rgb(204,204,204)">Patches 27 and 28 represent a revolutionary improvement in Object Browser</span></div><div><span style="color:rgb(204,204,204)">stability. We've transformed the component from crash-prone to rock-solid,</span></div><div><span style="color:rgb(204,204,204)">achieving better performance improvement while eliminating the most critical</span></div><div><span style="color:rgb(204,204,204)">crashes.</span></div><br><div><span style="color:rgb(204,204,204)">The architectural breakthroughs in thread safety and disposal management provide</span></div><div><span style="color:rgb(204,204,204)">a strong foundation for future development and have significantly improved the</span></div><div><span style="color:rgb(204,204,204)">reliability of the BASIC IDE.</span></div><br><div><span style="color:rgb(204,204,204)">Thanks to mentors for their invaluable guidance and collaboration throughout this</span></div><div><span style="color:rgb(204,204,204)">transformative period.</span></div><br><div><span style="color:rgb(204,204,204)">If there is any other way I could have done this better? Please let me know :)</span></div><br><div><span style="color:rgb(204,204,204)">I have also attached the txt file for this mail in case the diagrams go south.</span></div><br><div><span style="color:rgb(204,204,204)">**Previous Updates:**</span></div><div><span style="color:rgb(204,204,204)">- Week 1: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-May/093264.html">https://lists.freedesktop.org/archives/libreoffice/2025-May/093264.html</a></span></div><div><span style="color:rgb(204,204,204)">- Weeks 2-3: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-June/093362.html">https://lists.freedesktop.org/archives/libreoffice/2025-June/093362.html</a></span></div><div><span style="color:rgb(204,204,204)">- Week 4: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-June/093392.html">https://lists.freedesktop.org/archives/libreoffice/2025-June/093392.html</a></span></div><div><span style="color:rgb(204,204,204)">- Week 5: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-June/093443.html">https://lists.freedesktop.org/archives/libreoffice/2025-June/093443.html</a></span></div><div><span style="color:rgb(204,204,204)">- Week 6: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-July/093493.html">https://lists.freedesktop.org/archives/libreoffice/2025-July/093493.html</a></span></div><div><span style="color:rgb(204,204,204)">- Week 7: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-July/093527.html">https://lists.freedesktop.org/archives/libreoffice/2025-July/093527.html</a></span></div><div><span style="color:rgb(204,204,204)">- Week 8: <a href="https://lists.freedesktop.org/archives/libreoffice/2025-July/093572.html">https://lists.freedesktop.org/archives/libreoffice/2025-July/093572.html</a></span></div><br><br><br></div></div>