fix:LangCacheView::clear issue closes #590

src/dbzero/object_model/LangCache.cpp

@@ -297,32 +297,23 @@ namespace db0
 
     void LangCacheView::clear(bool expired_only, bool as_defunct)
     {
+        // copy for erase safety
+        auto objects = std::move(m_objects);
+        m_objects = {};
+
         // erase expired objects only
         if (expired_only) {
-            // optimized clear when lang cache view size >> cache size
-            if (m_objects.size() > m_cache.size() * 4) {                
-                std::unordered_set<Address> non_expired_objects;
-                for (auto addr: m_objects) {
-                    if (!m_cache.erase(m_fixture_id, addr, true, as_defunct)) {
-                        non_expired_objects.insert(addr);
-                    }
-                }
-                m_objects = std::move(non_expired_objects);
-            } else {
-                auto it = m_objects.begin();
-                while (it != m_objects.end()) {
-                    if (m_cache.erase(m_fixture_id, *it, true, as_defunct)) {
-                        it = m_objects.erase(it);
-                    } else {
-                        ++it;
-                    }                    
+            std::unordered_set<Address> non_expired_objects;
+            for (auto addr: objects) {
+                if (!m_cache.erase(m_fixture_id, addr, true, as_defunct)) {
+                    non_expired_objects.insert(addr);
                 }
             }
+            m_objects = std::move(non_expired_objects);
         } else {
-            for (auto addr: m_objects) {
+            for (auto addr: objects) {
                 m_cache.erase(m_fixture_id, addr, false, as_defunct);
-            }
-            m_objects.clear();
+            }            
         }
     }
 

src/dbzero/object_model/tags/ObjectIterable.hpp

@@ -128,7 +128,7 @@ namespace db0::object_model
         TypeObjectPtr getLangType() const;
 
         // NOTE: ObjectIterable might be related with a specific context / scope (e.g. snapshot)
-        // to prevend context deletion before the query, it's important to attach it
+        // to prevent context deletion before the query, it's important to attach it
         // otherwise a segfault might happen when query iterated over, after closing the context
         void attachContext(ObjectPtr) const;
 

src/dbzero/workspace/Fixture.cpp

@@ -387,7 +387,7 @@ namespace db0
             // Flush using registered flush handlers
             for (auto &handler: m_flush_handlers) {
                 handler();
-            }            
+            }              
             m_lang_cache.clear(true);
             // lock for exclusive access
             {

src/dbzero/workspace/GC0.cpp

@@ -283,5 +283,6 @@ namespace db0
 
     std::unique_ptr<GC0::CommitContext> GC0::beginCommit() {
         return std::make_unique<CommitContext>(*this);
-    }    
+    }
+
 }