#12902: Improve handle decoding error messages -------------------------------------+------------------------------------- Reporter: Profpatsch | Owner: Type: feature | Status: new request | Priority: normal | Milestone: Component: | Version: 8.0.1 libraries/base | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- When handle decoding encounters a byte sequence it cannot handle and `ErrorOnCodingFailure` is set, at the moment [https://hackage.haskell.org/package/base-4.9.0.0/docs/src/GHC.IO.Encoding.Fa... an IO error with a pretty non-descriptive messages is thrown] (`invalid byte sequence`). The user should get a bit more Information in that case: 1) What was the byte sequence that caused the error (and if possible where in the input, of course hard with handles) 2) A stack trace of the functions that caused this (probably from `hGetContents` and similar upwards It’s a very hard-to-debug error with the current implementation. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12902 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler