ghc's dwarf (-g) output does not like Unicode (Char.intToDigit: not a digit 136)

Easy to reproduce as:

inplace/bin/ghc-stage2 -w -g -c testsuite/tests/parser/unicode/utf8_024.hs
ghc-stage2: panic! (the 'impossible' happened)
  (GHC version 7.9.20141219 for x86_64-unknown-linux):
        Char.intToDigit: not a digit 136

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

petermw> Yes, Unicode doesn't work with DWARF yet

Trac metadata

Trac field	Value
Version	7.9
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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