Opened 5 years ago

Closed 5 years ago

Last modified 5 years ago

#6141 closed bug (invalid)

ghc: panic! (the 'impossible' happened)

Reported by: aSect Owned by:
Priority: normal Milestone:
Component: Compiler Version: 7.4.1
Keywords: Cc:
Operating System: Linux Architecture: x86_64 (amd64)
Type of failure: GHC rejects valid program Test Case:
Blocked By: Blocking:
Related Tickets: Differential Rev(s):
Wiki Page:


i tried to load the following code in ghci:

{-# OPTIONS_GHC -Wall -O2 #-}

module Main where

import Data.Map (Map) import qualified Data.Map as Map

data Vertex a

Vertex { vname :: a }

deriving (Show, Read, Eq)

data Edge a

Edge { xedge :: a

, yedge
a } deriving (Show, Read, Eq)

data Graph a

Graph { vertexes :: [Vertex a]

, edges
[Edge a]
, adjacents
Vertex a -> [Vertex a] } deriving (show, Read, Eq)

and then i got the following error:

ghc: panic! (the 'impossible' happened)

(GHC version 7.4.1 for x86_64-unknown-linux):

nameModule show{tv a25N}

Change History (2)

comment:1 Changed 5 years ago by aSect

Resolution: invalid
Status: newclosed

comment:2 Changed 5 years ago by guest

It was fixed by #5961.

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