stack overflow regression
I would like to teach GHC that <=
is transitive. I tried a module that looks like this:
{-# LANGUAGE GADTs, Rank2Types, TypeOperators #-}
import GHC.TypeLits
trans :: (a <= b, b <= c) => ((a <= c) => d) -> d
trans = undefined
In 7.8, this is a type error; in 7.10 the compiler thinks a long time before emitting a stack overflow exception.
Trac metadata
Trac field | Value |
---|---|
Version | 7.10.2 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |