setNumCapabilities broken in HEAD
import GHC.Conc
import Control.Monad
main :: IO ()
main = do
n <- getNumCapabilities
when (n == 1) $ setNumCapabilities 2
print ()
One would expect this program to print () just once, but when compiled with -O or -O2 it prints () repeatedly and indefinitely!
This doesn't happen on GHC 7.6.2 or 7.4.1, only on HEAD.
Trac metadata
Trac field | Value |
---|---|
Version | 7.7 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Runtime System |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |