[Haskell-cafe] Re: user error when using Text.Regex.PCRE

[ChrisK]

Thank you very much for the error report.  I have tracked down the cause.

You are searching against an empty Bytestring.  This is now represented by

> -- | /O(1)/ The empty 'ByteString'
> empty :: ByteString
> empty = PS nullForeignPtr 0 0

And while the useAsCString and useAsCStringLen functions never reveal the null
pointer, the current library uses unsafeUseAsCStringLen, which returns the null
pointer.

And this is getting caught by a null pointer check resulting in your crash.  I
will post a fix later tonight, and announce it.

Which regex-prce version are you using?  Perhaps from hackage?  I want to
prioritize the version you need fixed.

The earlier repository holds up to version 0.81 at
http://darcs.haskell.org/packages/regex-pcre/
The newer repository holds up to version 0.92 at
http://darcs.haskell.org/packages/regex-unstable/regex-pcre/regex-pcre.cabal

Out of further curiosity:

Which version of the pcre library does it use?
And what version of ghc?
Which version of Data.ByteString?

Cheers,
  Chris Kuklewicz