ghc: panic! (the 'impossible' happened)
Apparently not so impossible. I am just filling a bug following the advice of GHC.
Here's the error message coming out of GHC
ghc: panic! (the 'impossible' happened)
(GHC version 8.0.2 for x86_64-unknown-linux):
initTc: unsolved constraints
WC {wc_insol =
[W] liftIO_a2jc :: t_a2jb[tau:1] (CHoleCan: liftIO)
[W] handleMsg_a2k6 :: t_a2k5[tau:1] (CHoleCan: handleMsg)
[W] expectTimeout_a2kb :: t_a2ka[tau:1] (CHoleCan: expectTimeout)
[W] sendMsg_a2v9 :: t_a2v8[tau:1] (CHoleCan: sendMsg)
[W] tick_a2vc :: t_a2vb[tau:1] (CHoleCan: tick)}
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
And here the corresponding code that leads to this compilation error:
module Main where
import Control.Distributed.Process (NodeId (..), Process)
import Control.Monad (forever)
import Data.IORef (IORef, newIORef)
type Clock =
Int
emitRandomNumbers :: [NodeId] -> Process ()
emitRandomNumbers nodes = do
clock <-
liftIO $ newIORef (0 :: Clock)
forever $ do
msg <-
handleMsg <$> expectTimeout 0
sendMsg <$> tick
I am compiling on with GHC 8.0.2 on Ubuntu 16.04, here are a list of the install dependencies:
array 0.5.1.1
base 4.9.1.0
binary 0.8.3.0
bytestring 0.10.8.1
containers 0.5.7.1
data-accessor 0.2.2.7
deepseq 1.4.2.0
distributed-process 0.7.3
distributed-static 0.3.8
exceptions 0.8.3
getting-started 0.1.0.0
ghc-boot-th 8.0.2
ghc-prim 0.5.0.0
hashable 1.2.6.1
integer-gmp 1.0.0.1
mtl 2.2.1
network 2.6.3.2
network-transport 0.4.4.0
network-transport-tcp 0.5.1
pretty 1.1.3.3
random 1.1
rank1dynamic 0.3.3.0
rts 1.0
stm 2.4.4.1
syb 0.7
template-haskell 2.11.1.0
text 1.2.2.2
time 1.6.0.1
transformers 0.5.2.0
transformers-compat 0.5.1.4
unix 2.7.2.1
Let me know should you need any additional informations.
Trac metadata
Trac field | Value |
---|---|
Version | 8.0.2 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |