control characters in prompt lead to deadlock on 64 bit system

[phercek]

The problem seems to be in wcwidth foreign call where the result type was Int instead of CInt. This led to Int32/Int64 mismatch which later caused a deadlock or something like that.

I'm attaching a patch.

[phercek]

the fix of the bug

[judah]

Thanks for the patch! I've applied it to the repo at http://code.haskell.org/haskeline and released haskeline-0.6.4.5 which contains the fix for it.

For my future record: wcwidth is supposed to return -1 for the width of escape characters, which we handle as a separate case. But due to the 32/64-bit mismatch, it returned a very large size for their width. This caused an infinite loop in the line-breaking algorithm for wide characters.