Ambiguous record field name destructure on qualified imported modules causes compiler crash
I have two extremely simple files which will reproduce this crash.
Main.hs:
module Main where
import qualified B as B
x = 0
main :: IO ()
main = do let B.T { x = inside } = B.value
putStrLn (show inside)
B.hs
module B where
data T = T { x :: Bool }
value :: T
value = T { x = True }
I did a qualified import of one module into the main module. I tried to destructure a record from this module, but I didn't qualify the record fields in the destructuring expression.
The output of the compiler is below:
Building ghcbug-repro-0.1.0.0...
Preprocessing executable 'ghcbug-repro' for ghcbug-repro-0.1.0.0...
[2 of 2] Compiling Main ( Main.hs, dist/build/ghcbug-repro/ghcbug-repro-tmp/Main.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
Trac metadata
Trac field | Value |
---|---|
Version | 8.2.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
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Blocking | |
CC | |
Operating system | |
Architecture |