Greetings,
recently GHC-7.6.2 hung while compiling my program. I was able to minify
it to this:
{-# LANGUAGE ImplicitParams #-}
data D = D Int deriving Show
slow_to_compile :: IO ()
slow_to_compile = do
tst1 <- return 1
let ?tst1 = tst1
let ?tst2 = tst1
let ?tst3 = tst1
let ?tst4 = tst1
let ?tst5 = tst1
let ?tst6 = tst1
let ?tst7 = tst1
print $ D ?tst1
The compilation finishes actually. But it's very slow. The time depends
on number of implicit parameter bindings. Looks like it grows as
exponential function of it.
As a workaround you can explicitly specify type for tst1.
Is it a known issue?
Best regards,
Dmitry
_______________________________________________
ghc-devs mailing list
[email protected]
http://www.haskell.org/mailman/listinfo/ghc-devs
