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 |
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Differential revisions |
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BlockedBy |
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Related |
|
Blocking |
|
CC |
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Operating system |
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Architecture |
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