Added skipping of forward declarations

src/cx/cursor.h

@@ -130,6 +130,16 @@ public:
 
     bool is_declaration() const { return clang_isDeclaration(kind()); }
 
+    bool is_forward_declaration() const
+    {
+        auto definition = clang_getCursorDefinition(m_cursor);
+
+        if (clang_equalCursors(definition, clang_getNullCursor()))
+            return true;
+
+        return !clang_equalCursors(m_cursor, definition);
+    }
+
     bool is_invalid_declaration() const
     {
         return clang_isInvalidDeclaration(m_cursor);

src/uml/class_diagram_visitor.h

@@ -572,12 +572,16 @@ static enum CXChildVisitResult translation_unit_visitor(
         case CXCursor_ClassTemplate:
             [[fallthrough]];
         case CXCursor_ClassDecl: {
-            spdlog::info("Found class or class template declaration: {}",
-                cursor_name_str);
+            spdlog::info(
+                "Found class or class template declaration: {}", cursor);
             if (!ctx->config.should_include(cursor.fully_qualified())) {
                 ret = CXChildVisit_Continue;
                 break;
             }
+            if (cursor.is_forward_declaration()) {
+                ret = CXChildVisit_Continue;
+                break;
+            }
 
             scope = scope_t::kPublic;