foreign exports not taken into account when calculating -fwarn-unused-imports
Here we have a program that imports and uses liftM from Control.Monad, but only as a result of being used in the definition of a function that is foreign exported.
module Foo () where
import Control.Monad (liftM)
foo :: IO ()
foo = id `liftM` return ()
foreign export ccall "hs_foo"
foo :: IO ()GHC 6.6 and HEAD report:
foo.hs:3:0:
Warning: Module `Control.Monad' is imported, but nothing from it is used,
except perhaps instances visible in `Control.Monad'
To suppress this warning, use: import Control.Monad()So I suppose all that needs to happen is to add in foreign exports as roots when building the usage graph.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.7 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | Unknown |
| Architecture | Unknown |