#11983: Can't use IntPtr or WordPtr in a foreign import
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Reporter: RyanGlScott | Owner: RyanGlScott
Type: bug | Status: new
Priority: normal | Milestone: 8.2.1
Component: Compiler | Version: 8.0.1
(FFI) |
Keywords: | Operating System: Unknown/Multiple
Architecture: | Type of failure: GHC rejects
Unknown/Multiple | valid program
Test Case: | Blocked By:
Blocking: | Related Tickets: #3008, #5529
Differential Rev(s): | Wiki Page:
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Despite the [http://hackage.haskell.org/package/base-4.8.2.0/docs/Foreign-
Ptr.html#t:IntPtr docs claiming] that you can use `IntPtr` and `WordPtr`
to convert to and from `intptr_t` and `uintptr_t`, you can't actually do
so in a `foreign import` as of GHC 7.6. Here's a minimal example:
{{{#!hs
-- Example.hs
{-# LANGUAGE ForeignFunctionInterface #-}
module Example where
{-# INCLUDE example.h #-}
import Foreign.Ptr
foreign import ccall "intptr_example"
intPtrExample :: IntPtr -> IO ()
foreign import ccall "uintptr_example"
wordPtrExample :: WordPtr -> IO ()
}}}
{{{#!c
// example.h
#ifndef EXAMPLE_H
#define EXAMPLE_H
#include