ghci panic: thread blocked indefinitely in an MVar operation
I stumbled across this error today:
phil ~
$ ghci
GHCi, version 6.12.3: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
Prelude>
[1]+ Stopped ghci
phil ~
$ fg
ghci
^C^C
Prelude>
ghc: panic! (the 'impossible' happened)
(GHC version 6.12.3 for i386-apple-darwin):
thread blocked indefinitely in an MVar operation
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
phil ~
$
Steps to reproduce:
- start ghci
- ctrl-z
- fg
- ctrl-c
- ctrl-c
- enter
- wait ~2 seconds
I'm not sure if it is related but while waiting for the impossible to happen, any characters typed are not echoed to the screen.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.12.3 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | GHCi |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | MacOS X |
| Architecture | x86 |