source file that compiled fine fails to recompile after touching it (yes, another one)
I'm using the development snapshot ghc-6.11.20090107
and ran into a bug very similar to #2888 (closed), but I think it is different because I could not reproduce that bug in my version.
The setup is very similar: File A.hs
contains
{-# LANGUAGE TypeFamilies #-}
module A where
class Foo a where
data Bar a :: * -> *
and file B.hs
contains
{-# LANGUAGE TypeFamilies #-}
module B where
import A
instance Foo Int where
data Bar Int x where
Baz :: Bar Int String
Then:
rwbarton@functor:/tmp/a$ ghc --make B
[1 of 2] Compiling A ( A.hs, A.o )
[2 of 2] Compiling B ( B.hs, B.o )
rwbarton@functor:/tmp/a$ touch B.hs
rwbarton@functor:/tmp/a$ ghc --make B
[2 of 2] Compiling B ( B.hs, B.o )
B.hs:8:2:
Arguments that do not correspond to a class parameter must be variables
Instead of a variable, found Int
In the associated type instance for `Bar'
In the instance declaration for `Foo Int'
Trac metadata
Trac field | Value |
---|---|
Version | 6.11 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |