Unboxed tuples as values
Consider
type T a = Int -> (# Int, Int #)
f :: T a -> T a
f t = \x -> case t x of r -> r
gives the following error message:
ghc-5.04.1: panic! (the `impossible' happened, GHC
version 5.04.1):
codeGen/CgRetConv.lhs:83: Non-exhaustive
patterns in function
dataReturnConvPrim
Trouble is that 'r' is bound to an unboxed tuple. This
should fail, but in 5.04.1 it crashes the compiler. In 6.0
it's worse: the code will core dump because it enters R1.
But it should be rejected in the type checker.
Trac metadata
| Trac field | Value |
|---|---|
| Version | None |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | ResolvedFixed |
| Component | Compiler (Type checker) |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |