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 |
|
