Fix exception during cnex stack unwind when no debug information exists.
Fix exception during cnex stack unwind when no debug information exists.

ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang,ghewgill/neon-lang