#9163: Ptr should have a phantom role -------------------------------------+------------------------------------ Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Comment (by nomeata): I tried it, and hPutBuf & Co are called with `Ptr Word8` (sometimes called `LitString`) in all cases but `BufWrite.bPutCStringLen`, where we have a `Ptr CChar`, where `CChar` is a newtype. So by using `coerce` there (and `unsafeCoerce` during bootstrapping), we get the best of boths worlds: The more restrictive role and the free behaviour. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9163#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler