#4309: Painfully large errors with silly GADT instances
---------------------------------+------------------------------------------
Reporter: pumpkin | Owner:
Type: bug | Status: new
Priority: normal | Component: Compiler
Version: 6.12.3 | Keywords:
Testcase: | Blockedby:
Os: Unknown/Multiple | Blocking:
Architecture: Unknown/Multiple | Failure: None/Unknown
---------------------------------+------------------------------------------
If (for whatever reason) you decide to ask GHC to derive (using
StandaloneDeriving) silly instances for GADTs, like maybe Ord on a GADT
that refines its parameters to incompatible types for different
constructors, the automatic deriving mechanism fails with massive errors.
The attached file gives me 301 lines of errors in GHCi, as it seems to
print all the generated code, and the generated code increases in size
with the number of constructors of the datatype. I have a large GADT in a
project of mine with a couple hundred constructors, and it gave me over
8000 lines of errors.
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4309>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler
_______________________________________________
Glasgow-haskell-bugs mailing list
[email protected]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
