#227 Crash when using IndexReader::reopen()

[Benjamin Weikmann]

Version: 2.3.3.4

1. Creating IndexWriter and IndexReader/IndexSearch of an index directory
2. Inserting and deleting from index, calling IndexReader::reopen() after that without problems
3. Searching in index, so that IndexReader loads segment files into memory
4. Inserting and deleting from index so that index gets changed
5. Crash in call to IndexReader::reopen()
   File: MultiSegmentsReader.cpp, line 165
   Code: ((SegmentReader)(subReaders)[i])->_norms.get(field)
   What: Call to _norms.get()-Method with a null pointer
   Context: copying unchanged norms from the old normsCache to the new one (comment)

Does anybody have an idea?