#8266: Dynamic linking on Mac --------------------------------------------+------------------------------ Reporter: kazu-yamamoto | Owner: Type: bug | thoughtpolice Priority: highest | Status: closed Component: Build System | Milestone: 7.8.1 Resolution: fixed | Version: 7.7 Operating System: MacOS X | Keywords: Type of failure: GHC doesn't work at all | Architecture: Test Case: | Unknown/Multiple Blocking: | Difficulty: Unknown | Blocked By: | Related Tickets: --------------------------------------------+------------------------------ Comment (by darchon): The latest patch makes Mach-O (currently just Darwin, not iOS) behave the same as ELF in terms of dynamic linking. That is, all dynamic library locations are now relative to `@rpath`, and GHC adds `LC_RPATH` commands for every directory containing the dependent libraries. This enables the use-case of using `cabal -w inplace/bin/ghc-stage2`. Cabal will however need an update as well, as libraries installed by Cabal will still use absolute paths: {{{ -- Installed by GHC install @rpath/package1.dylib @rpath/package2.dylib @rpath/package3.dylib -- Installed by Cabal /absolute_path_to_library/package4.dylib /absolute_path_to_library/package5.dylib }}} By applying the following patch to Cabal: {{{ diff --git a/Cabal/Distribution/Simple/GHC.hs b/Cabal/Distribution/Simple/GHC.hs index c7ea633..78cdcbb 100644 --- a/Cabal/Distribution/Simple/GHC.hs +++ b/Cabal/Distribution/Simple/GHC.hs @@ -867,11 +867,6 @@ buildOrReplLib forRepl verbosity pkg_descr lbi lib clbi = do ghcOptDynLinkMode = toFlag GhcDynamicOnly, ghcOptInputFiles = dynamicObjectFiles, ghcOptOutputFile = toFlag sharedLibFilePath, - -- For dynamic libs, Mac OS/X needs to know the install location - -- at build time. - ghcOptDylibName = if buildOS == OSX - then toFlag sharedLibInstallPath - else mempty, ghcOptPackageName = toFlag pkgid, ghcOptNoAutoLinkPackages = toFlag True, ghcOptPackageDBs = withPackageDB lbi, }}} The situation will change to: {{{ -- Installed by GHC install @rpath/package1.dylib @rpath/package2.dylib @rpath/package3.dylib -- Installed by Cabal @rpath/package4.dylib @rpath/package5.dylib }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8266#comment:31 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler