config.cache is created when you pass -C to configure, which speeds it up considerably (3.5s vs 16.5 on my laptop). It would be nice to just ignore the cache file it generates.
Originally this patch also ignored the regression output files, until I realized why that was a bad idea. Add a comment about that.
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Jim Nasby, Data Architect, Blue Treble Consulting
Data in Trouble? Get it in Treble! http://BlueTreble.com