#13973: NamedFieldPuns fails for qualified imports if field name is already in scope -------------------------------------+------------------------------------- Reporter: sergv | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Poor/confusing | Unknown/Multiple error message | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by sergv): * failure: Compile-time crash or panic => Poor/confusing error message Old description:

Hi, I get following error on the program below

{{{ Package has never been configured. Configuring with default flags. If this fails, please run configure manually. Resolving dependencies... Configuring test-0.1.0.0... Building test-0.1.0.0... Preprocessing library test-0.1.0.0... [1 of 2] Compiling Record ( Record.hs, dist/build/Record.o ) [2 of 2] Compiling Test ( Test.hs, dist/build/Test.o )

<no location info>: error: ghc: panic! (the 'impossible' happened) (GHC version 8.0.2 for x86_64-unknown-linux): translateConPatVec: lookup

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

The cabal project: {{{ name: test version: 0.1.0.0 cabal-version: >= 1.16 build-type: Simple

library exposed-modules: Record Test default-language: Haskell98 build-depends: base >= 4.7 }}}

The module `Record.hs`: {{{#!hs module Record (Record(..)) where

data Record = Record { field1 :: Int, field2 :: Int } }}}

The main module `Test.hs`: {{{#!hs {-# LANGUAGE NamedFieldPuns #-}

module Test (foo) where

import qualified Record as Rec

-- The culprit field2 :: () field2 = ()

foo :: Rec.Record -> Int foo Rec.Record{Rec.field1, field2} = field1 + field2 }}}

New description: Hi, I get following error on the program below {{{ Package has never been configured. Configuring with default flags. If this fails, please run configure manually. Resolving dependencies... Configuring test-0.1.0.0... Building test-0.1.0.0... Preprocessing library test-0.1.0.0... [1 of 2] Compiling Record ( Record.hs, dist/build/Record.o ) [2 of 2] Compiling Test ( Test.hs, dist/build/Test.o ) <no location info>: error: ghc: panic! (the 'impossible' happened) (GHC version 8.0.2 for x86_64-unknown-linux): translateConPatVec: lookup Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} The cabal project: {{{ name: test version: 0.1.0.0 cabal-version: >= 1.16 build-type: Simple library exposed-modules: Record Test default-language: Haskell98 build-depends: base >= 4.7 }}} The module `Record.hs`: {{{#!hs module Record (Record(..)) where data Record = Record { field1 :: Int, field2 :: Int } }}} The main module `Test.hs`: {{{#!hs {-# LANGUAGE NamedFieldPuns #-} module Test (foo) where import qualified Record as Rec -- The culprit field2 :: () field2 = () foo :: Rec.Record -> Int foo Rec.Record{Rec.field1, field2} = field1 + field2 }}} The program is invalid - named field `field2` should be written as `Rec.field2`, however I'd expect more informative error message instead of panic. -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13973#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler