#16367: Panic when trying to openFile with -fdefer-type-errors ----------------------------------+-------------------------------------- Reporter: vilem | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: GHCi | Version: 8.4.4 Resolution: | Keywords: Operating System: MacOS X | Architecture: x86_64 (amd64) Type of failure: Runtime crash | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | ----------------------------------+-------------------------------------- Changes (by vilem): * version: 8.4.3 => 8.4.4 Old description:

{{{ $ stack repl

Note: No local targets specified, so a plain ghci will be started with no package hiding or package options.

If you want to use package hiding and options, then you can try one of the following:

* If you want to start a different project configuration than /Users/vl200/.stack/global-project/stack.yaml, then you can use stack init to create a new stack.yaml for the packages in the current directory.

* If you want to use the project configuration at /Users/vl200/.stack/global-project/stack.yaml, then you can add to its 'packages' field.

Configuring GHCi with the following packages: GHCi, version 8.4.3: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from /Users/vl200/.ghci Loaded GHCi configuration from /private/var/folders/km/1g5b7h891674vhv9z1g4d9cw0000gn/T/haskell-stack- ghci/2a3bbd58/ghci-script Prelude> import System.IO Prelude System.IO> openFile ".g .granule .gitignore .ghc .ghci .gitconfig Prelude System.IO> openFile ".granule" Re Read ReadMode ReadS ReadWriteMode Real RealFloat RealFrac RelativeSeek Prelude System.IO> openFile ".granule" ReadMode ghc: panic! (the 'impossible' happened) (GHC version 8.4.3 for x86_64-apple-darwin): nameModule system $dShow_a1QJ Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in ghc:Outputable pprPanic, called at compiler/basicTypes/Name.hs:241:3 in ghc:Name

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

New description: {{{ ~ ✔︎ ghci GHCi, version 8.4.4: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from /Users/vl200/.ghci Prelude> :set -fdefer-type-errors Prelude> import System.IO Prelude System.IO> openFile ".granule" ReadWriteMode ghc: panic! (the 'impossible' happened) (GHC version 8.4.4 for x86_64-apple-darwin): nameModule system $dShow_a1QU Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in ghc:Outputable pprPanic, called at compiler/basicTypes/Name.hs:241:3 in ghc:Name Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} But works fine when I don't :set that option. {{{ ~ ✔︎ ghci GHCi, version 8.4.4: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from /Users/vl200/.ghci Prelude> import System.IO Prelude System.IO> openFile ".granule" ReadWriteMode {handle: .granule} Prelude System.IO> }}} -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16367#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler