ghc panic: ToDo: Match.viewLExprEq
The attached test-case triggers a
ghc: panic! (the 'impossible' happened)
(GHC version 7.0.0.20100924 for x86_64-unknown-linux):
ToDo: Match.viewLExprEq
this is a regression from 6.12.3 where there was no problem.
In the function Match.viewLExprEq one case is not defined however the comments say viewLExprEq may safely return False, so this is bug is probably trivial to fix ?
The testcase uses a combination of ViewPatterns and a cast from Data.Typeable.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | fontaine@cs.uni-duesseldorf.de |
| Operating system | |
| Architecture |