[GHC] #7603: Bad magic in static (FFI) object (7.6.1 for x86_64-apple-darwin)

[GHC]

#7603: Bad magic in static (FFI) object (7.6.1 for x86_64-apple-darwin)
-------------------------------+--------------------------------------------
Reporter:  morabbin            |          Owner:                
    Type:  bug                 |         Status:  new           
Priority:  normal              |      Component:  Compiler      
 Version:  7.6.1               |       Keywords:                
      Os:  MacOS X             |   Architecture:  x86_64 (amd64)
 Failure:  Compile-time crash  |      Blockedby:                
Blocking:                      |        Related:                
-------------------------------+--------------------------------------------
 When spraying [http://code.google.com/p/hoc/ HOC] (Haskell to Objective-C)
 for bitrot, I encountered a GHC panic during the loading of some FFI.

 Judging by the log below, it looks like this is during a TH execution, so
 the problem may be bitrot in this code wrt TH. Quite happy to dig further
 myself if pointed in the right direction.

 {{{
 Orac:~/work/hoc-read-only/hoc $ cabal build
 Compiling HOC_cbits...
 Building HOC-1.0...
 Preprocessing library HOC-1.0...
 [16 of 31] Compiling HOC.Invocation   ( HOC/HOC/Invocation.hs,
 dist/build/HOC/Invocation.o )

 HOC/HOC/Invocation.hs:14:1:
     Unacceptable argument type in foreign declaration: FFICif
     When checking declaration:
       foreign import ccall safe "static Invocation.h callWithExceptions"
 c_callWithExceptions
         :: FFICif
            -> FunPtr a -> Ptr b -> Ptr (Ptr ()) -> IO (Ptr ObjCObject)
 Orac:~/work/hoc-read-only/hoc $ cabal build
 Compiling HOC_cbits...
 Building HOC-1.0...
 Preprocessing library HOC-1.0...
 [ 7 of 31] Compiling HOC.FFICallInterface ( HOC/HOC/FFICallInterface.hs,
 dist/build/HOC/FFICallInterface.o )
 [ 8 of 31] Compiling HOC.Arguments    ( HOC/HOC/Arguments.hs,
 dist/build/HOC/Arguments.o ) [HOC.FFICallInterface changed]
 [11 of 31] Compiling HOC.CStruct      ( HOC/HOC/CStruct.hs,
 dist/build/HOC/CStruct.o ) [HOC.FFICallInterface changed]
 [13 of 31] Compiling HOC.ID           ( HOC/HOC/ID.hs, dist/build/HOC/ID.o
 ) [HOC.FFICallInterface changed]
 [16 of 31] Compiling HOC.Invocation   ( HOC/HOC/Invocation.hs,
 dist/build/HOC/Invocation.o )
 [17 of 31] Compiling HOC.ExternFunctions ( HOC/HOC/ExternFunctions.hs,
 dist/build/HOC/ExternFunctions.o )

 HOC/HOC/ExternFunctions.hs:77:34:
     Ambiguous occurrence `unsafePerformIO'
     It could refer to either `Foreign.unsafePerformIO',
                              imported from `Foreign' at
 HOC/HOC/ExternFunctions.hs:10:1-14
                           or `System.IO.Unsafe.unsafePerformIO',
                              imported from `System.IO.Unsafe' at
 HOC/HOC/ExternFunctions.hs:11:1-23
                              (and originally defined in `GHC.IO')
 Orac:~/work/hoc-read-only/hoc $ cabal build
 Compiling HOC_cbits...
 Building HOC-1.0...
 Preprocessing library HOC-1.0...
 [17 of 31] Compiling HOC.ExternFunctions ( HOC/HOC/ExternFunctions.hs,
 dist/build/HOC/ExternFunctions.o )
 [18 of 31] Compiling HOC.StdArgumentTypes ( HOC/HOC/StdArgumentTypes.hs,
 dist/build/HOC/StdArgumentTypes.o )
 Loading package ghc-prim ... linking ... done.
 Loading package integer-gmp ... linking ... done.
 Loading package base ... linking ... done.
 Loading package array-0.4.0.1 ... linking ... done.
 Loading package deepseq-1.3.0.1 ... linking ... done.
 Loading package containers-0.5.0.0 ... linking ... done.
 Loading package pretty-1.1.1.0 ... linking ... done.
 Loading package template-haskell ... linking ... done.
 Loading package syb-0.3.7 ... linking ... done.
 Loading package bytestring-0.10.0.0 ... linking ... done.
 Loading package transformers-0.3.0.0 ... linking ... done.
 Loading package mtl-2.1.2 ... linking ... done.
 Loading package text-0.11.2.3 ... linking ... done.
 Loading package parsec-3.1.3 ... linking ... done.
 Loading package old-locale-1.0.0.5 ... linking ... done.
 Loading package old-time-1.1.0.1 ... linking ... done.
 Loading package fgl-5.4.2.4 ... linking ... done.
 Loading package filepath-1.3.0.1 ... linking ... done.
 Loading package time-1.4.0.1 ... linking ... done.
 Loading package unix-2.6.0.0 ... linking ... done.
 Loading package directory-1.2.0.0 ... linking ... done.
 Loading package binary-0.5.1.1 ... linking ... done.
 Loading package HUnit-1.2.5.1 ... linking ... done.
 Loading object (static) dist/build/HOC_cbits.o ... ghc:
 dist/build/HOC_cbits.o: Bad magic. Expected: feedfacf, got: feedface.

 ghc: panic! (the 'impossible' happened)
   (GHC version 7.6.1 for x86_64-apple-darwin):
         loadObj "dist/build/HOC_cbits.o": failed

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7603>
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