Make sure we also reserve space for destination and pronunciation

src/extractor/extraction_containers.cpp

@@ -47,7 +47,9 @@ ExtractionContainers::ExtractionContainers()
 {
     // Check if stxxl can be instantiated
     stxxl::vector<unsigned> dummy_vector;
-    // Insert the empty string, it has no data and is zero length
+    // Insert three empty strings for name, destination and pronunciation
+    name_lengths.push_back(0);
+    name_lengths.push_back(0);
     name_lengths.push_back(0);
 }
 

src/extractor/extractor_callbacks.cpp

@@ -27,6 +27,7 @@ namespace extractor
 ExtractorCallbacks::ExtractorCallbacks(ExtractionContainers &extraction_containers)
     : external_memory(extraction_containers)
 {
+    // we reserved 0, 1, 2 for the empty case
     string_map[MapKey("", "")] = 0;
 }