Incorrect warning about qualified import
GHC HEAD failed to validate recently because of this warning (in combination with -Werror
)
Distribution/Simple/Program.hs:222:24:
Warning: This binding for `update' shadows the existing binding
imported from Distribution.Compat.Map at Distribution/Simple/Program.hs:87:0-46
In the definition of `updateUnconfiguredProgs'
The code it was warning about looks like
updateUnconfiguredProgs update conf =
conf { unconfiguredProgs = update (unconfiguredProgs conf) }
So initially it looks sensible. However the only import of Distribution.Compat.Map
in that module is from
import qualified Distribution.Compat.Map as Map
So actually there is no update
in scope at all and thus there is no name shadowing. The warning is incorrect.
This is a regression in ghc-6.9. The warning is not present with ghc-6.8.2.
It should be possible to reproduce this problem using ghc's branch of the Cabal lib and by reverting the patch that is currently masking the incorrect warning:
Fri Jan 18 11:12:30 PST 2008 Ian Lynagh <igloo@earth.li>
* Fix warnings in Cabal
Trac metadata
Trac field | Value |
---|---|
Version | 6.9 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | Unknown |
Architecture | Unknown |