Add TODO note

src/Composer/DependencyResolver/PoolBuilder.php

@@ -72,6 +72,9 @@ class PoolBuilder
             }
         }
 
+        // TODO make sure if a fixed package replaces X packages they are not loaded again in loadNames
+        //  perhaps loadPackage needs to mark them as loadedNames when loading a fixed package?
+
         foreach ($request->getRequires() as $packageName => $constraint) {
             if (isset($this->loadedNames[$packageName])) {
                 continue;