[GHC] #3741: ghci misinterprets "early" unicode characters

[GHC]

#3741: ghci misinterprets "early" unicode characters
----------------------------------------+-----------------------------------
  Reporter:  brian                      |          Owner:  igloo           
      Type:  merge                      |         Status:  new             
  Priority:  normal                     |      Milestone:  6.12.2          
 Component:  Compiler (Parser)          |        Version:  6.10.4          
Resolution:                             |       Keywords:                  
Difficulty:                             |             Os:  Unknown/Multiple
  Testcase:                             |   Architecture:  Unknown/Multiple
   Failure:  GHC rejects valid program  |  
----------------------------------------+-----------------------------------
Changes (by simonmar):

  * owner:  simonmar => igloo
  * type:  bug => merge

Comment:

 Fixed:

 {{{
 Thu Dec 10 16:09:09 GMT 2009  Simon Marlow <marlowsd at gmail.com>
   * Fix #3741, simplifying things in the process
   The problem in #3741 was that we had confused column numbers with byte
   offsets, which fails in the case of UTF-8 (amongst other things).
   Fortunately we're tracking correct column offsets now, so we didn't
   have to make a calculation based on a byte offset.  I got rid of two
   fields from the PState (last_line_len and last_offs).and one field
   from the AI (alex input) constructor.
 }}}

 This relies on Igloo's column number changes, which are apparently not in
 the 6.12 branch though.  It might be possible to merge this by just
 modifying advanceSrcLoc, without merging in the rest of the column number
 changes.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3741#comment:2>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler