[CLucene-dev] How to fix corrupt index?

[John O'B. <joh...@cr...>]

Hi,
	Hopefully someone on here might be able to point me in the right
direction to fix a corrupt index.
We use Clucene 0.9.20 in our search engine. One of the indexes appears to
have become corrupt. We tried using the Java Lucene CheckIndex tool to fix
the corruption(s). CheckIndex detected 1 broken segment and removed 162
docments and wrote a new segments file. Subsequent runs of CheckIndex report
"No problems were detected with this index.". However our search engine
still crashes when its performing a search on the "fixed" index. Here is the
relevant backtrace:

#8  0x001c0faa in lucene::index::SegmentTermDocs::read (this=0x664f26c8, 
    docs=0x664f9944, freqs=0x664f99c4, length=32)
    at CLucene/util/BitSet.h:35
#9  0x001b4a4a in lucene::index::MultiTermDocs::read (this=0x664e5d38, 
    docs=0x664f9944, freqs=0x664f99c4, length=32)
    at ../src/CLucene/index/MultiReader.cpp:400
#10 0x001ef7dc in lucene::search::TermScorer::next (this=0x664f9920)
    at ../src/CLucene/search/TermScorer.cpp:41
#11 0x001d2d23 in lucene::search::BooleanScorer::next (this=0x665f2fc0)
    at ../src/CLucene/search/BooleanScorer.cpp:63
#12 0x001d2d23 in lucene::search::BooleanScorer::next (this=0x664e5ec8)
    at ../src/CLucene/search/BooleanScorer.cpp:63
#13 0x001e3275 in lucene::search::IndexSearcher::_search (
    this=0x65ba6410, query=0x66734ed8, filter=0x0, nDocs=100)
    at ../src/CLucene/search/Scorer.h:39
#14 0x001e1fb0 in lucene::search::Hits::getMoreDocs (this=0x66881440, 
    m=50) at ../src/CLucene/search/Hits.cpp:110
#15 0x001e1acf in lucene::search::Hits::Hits ()
    at CLucene/util/PriorityQueue.h:35

We tried to perform a search using Luke tool but this also resulted in an
error. 
Also tried after optimizing the index db, but the same error persists. 
So it looks like the index db is still corrupt.

Has anyone come across an index corruption which results in similar
backtrace?
Any ideas as to why CheckIndex appears not to have detected/fixed all
corruptions?
Are there any other suggestions as to how to detect/repair index
corruptions?

Thanks in advance,
John.

P.s. I still have the index in question before and after running CheckIndex
fix on it so if anyone's willing to take a look at it I can upload it
somewhere for you to download.