Panic with (bogus?) deriving in hs-boot: newTyConEtadArity
$ cat A.hs
module Main where
import {-# SOURCE #-} B
main = return ()
$ cat B.hs
module B where
data Foo a = Foo a
deriving (Functor)
$ cat B.hs-boot
module B where
data Foo a
deriving (Functor)
$ ghc --make A.hs
[1 of 3] Compiling B[boot] ( B.hs-boot, B.o-boot )
ghc: panic! (the 'impossible' happened)
(GHC version 8.2.1 for i386-unknown-linux):
newTyConEtadArity
Foo
Call stack:
CallStack (from HasCallStack):
prettyCurrentCallStack, called at compiler/utils/Outputable.hs:1133:58 in ghc:Outputable
callStackDoc, called at compiler/utils/Outputable.hs:1137:37 in ghc:Outputable
pprPanic, called at compiler/types/TyCon.hs:2149:27 in ghc:TyCon
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 |
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Differential revisions |
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BlockedBy |
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Related |
|
Blocking |
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CC |
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Operating system |
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Architecture |
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