internal error: resurrectThreads: thread blocked in a strange way: 12

With 6.13.20100428:

w.hs:

module Main where

import Control.Concurrent ( forkIO, killThread )
import Control.Exception  ( block )

main :: IO ()
main = do tid <- block $ forkIO $ let x = x in x
          killThread tid

$ ghc --make -O w -threaded -fforce-recomp
[1 of 1] Compiling Main             ( w.hs, w.o )
Linking w ...
$ ./w
w: internal error: resurrectThreads: thread blocked in a strange way: 12
    (GHC version 6.13.20100428 for x86_64_unknown_linux)
    Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
zsh: abort      ./w

Trac metadata

Trac field	Value
Version	6.12.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	high
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture