Re: [Haskell-cafe] Calling Haskell from C

Answering my own question:

export DYLD_LIBRARY_PATH=/Users/dom/Library/Haskell/ghc-8.0.1/lib/test-via-c-0.1.0.0/bin:/Library/Frameworks/GHC.framework/Versions/8.0.1-x86_64/usr/lib/ghc-8.0.1/rts

./a.out 2500 2500 2500 2500 2500

On 13 Jan 2017, at 10:59, Dominic Steinitz wrote:

I've been trying to get the example in https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/ffi-chap.htm... https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/ffi-chap.htm... working.

I have a cabal file

name: test-via-c version: 0.1.0.0 homepage: TBD license: MIT author: Dominic Steinitz maintainer: idontgetoutmuch@gmail.com mailto:idontgetoutmuch@gmail.com category: System build-type: Simple cabal-version: >=1.10

executable Foo.dylib main-is: Foo.hs other-extensions: ForeignFunctionInterface build-depends: base >=4.7 && <4.10, primitive >=0.6 && <0.7 hs-source-dirs: src default-language: Haskell2010 include-dirs: src ghc-options: -O2 -shared -fPIC -dynamic extra-libraries: HSrts-ghc8.0.1

which installs

/Users/dom/Library/Haskell/ghc-8.0.1/lib/test-via-c-0.1.0.0/bin/Foo.dylib

I then compile the C with

gcc-6 Bar.c /Users/dom/Library/Haskell/ghc-8.0.1/lib/test-via-c-0.1.0.0/bin/Foo.dylib -I/Library/Frameworks/GHC.framework/Versions/8.0.1-x86_64/usr/lib/ghc-8.0.1/include -L/Library/Frameworks/GHC.framework/Versions/8.0.1-x86_64/usr/lib/ghc-8.0.1/rts -lHSrts-ghc8.0.1

Sadly when I try to run the executable I get

~/Dropbox/Private/TestU01-1.2.3/examples/src $ ./a.out dyld: Library not loaded: @rpath/Foo.dylib Referenced from: /Users/dom/Dropbox/Private/TestU01-1.2.3/examples/src/./a.out Reason: image not found Trace/BPT trap: 5

I am guessing the executable is looking for the dynamic library. I copied Foo.dylib to the current directory but still get the same error.

I know this is really an OS X question but I am hoping someone who has done before will be able to help.

Dominic Steinitz dominic@steinitz.org mailto:dominic@steinitz.org http://idontgetoutmuch.wordpress.com http://idontgetoutmuch.wordpress.com/

Dominic Steinitz dominic@steinitz.org http://idontgetoutmuch.wordpress.com