panic: ctFlavId: derived constraint cannot have id
When trying to check, whether GHC-7.5 still suffers from #5970 (closed) I found another bug: When I compile the attached module I get the type error:
ghc: panic! (the 'impossible' happened)
(GHC version 7.5.20120426 for i386-unknown-linux):
ctFlavId: derived constraint cannot have id
pty = llvm-extra-0.4:LLVM.Extra.Extension.X86.Add'{tc rj}
llvm-extra-0.4:LLVM.Extra.Extension.X86.D1{tc ri}
llvm-extra-0.4:LLVM.Extra.Extension.X86.D1{tc ri}
llvm-extra-0.4:LLVM.Extra.Extension.X86.D2{tc rh}
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
I tried hard to simplify the example and to remove all dependencies (llvm, type-level), but the test case is still rather involved.
Unfortunately it is again a problem with functional dependencies and I want to get rid of them anyway, but instead switching to type families and then to type level natural numbers I prefer to switch to type level numbers immediately.
Trac metadata
Trac field | Value |
---|---|
Version | 7.5 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |