There is a port of Lucene to C++, CLucene[1], it's compatible with version 2.3 of Java Lucene, the project is stopped long time ago, but it's very much stable, and works perfectly.
An other port which is compatible with version 3 of java Lucene is LucenePlusPlus, but it use a lot of boost's smart pointers, the port seems like t was automated. This port was why CLucene development stopped, the maintainers wanted to make this new port faster by not using smart pointers whenever possible, but that didn't happen.
Oddly enough, I don't see anyone talking about benchmarks for those projects. I found one offhand comment saying it was 2-3 faster than Java for indexing, but only 10% better for search. No real benchmarks or such. I suppose that's not the only reason to want a non-JVM version but it seems like a pretty major reason and something that'd warrant headline treatment in the readme...
1: http://sourceforge.net/projects/clucene 2: https://github.com/luceneplusplus/LucenePlusPlus