Machine: an Intel Core 2 Duo desktop Mac. OS: Mac OS X 10.7.4 Xcode: 4.6.1 (including command line tools) Haskell: "Haskell Platform 2012.4.0.0 64bit.pkg" downloaded today (GHC 7.4.2) cabal update advised me to install a new cabal-install. m% cabal install cabal-install Resolving dependencies... Downloading Cabal-1.16.0.3... [ 1 of 65] Compiling Distribution.Compat.Exception ( /var/folders/_n/5bc02hb51d361crtq41g_gc4000g8p/T/Cabal-1.16.0.3-85340/Cabal-1.16.0.3/Distribution/Compat/Exception.hs, /var/folders/_n/5bc02hb51d361crtq41g_gc4000g8p/T/Cabal-1.16.0.3-85340/Cabal-1.16.0.3/dist/setup/Distribution/Compat/Exception.o ) <<< snip >>> [52 of 67] Compiling Distribution.Simple.Build.PathsModule ( Distribution/Simple/Build/PathsModule.hs, dist/build/Distribution/Simple/Build/PathsModule.o ) Distribution/Simple/Build/PathsModule.hs:210:19: Warning: Pattern match(es) are non-exhaustive In a case alternative: Patterns not matched: PPC PPC64 Sparc Arm ... [53 of 67] Compiling Distribution.Simple.GHC ( Distribution/Simple/GHC.hs, dist/build/Distribution/Simple/GHC.o ) <<< snip >>> [65 of 65] Compiling Main ( /var/folders/_n/5bc02hb51d361crtq41g_gc4000g8p/T/Cabal-1.16.0.3-85340/Cabal-1.16.0.3/Setup.hs, /var/folders/_n/5bc02hb51d361crtq41g_gc4000g8p/T/Cabal-1.16.0.3-85340/Cabal-1.16.0.3/dist/setup/Main.o ) Linking /var/folders/_n/5bc02hb51d361crtq41g_gc4000g8p/T/Cabal-1.16.0.3-85340/Cabal-1.16.0.3/dist/setup/setup ... Configuring Cabal-1.16.0.3... Building Cabal-1.16.0.3... Preprocessing library Cabal-1.16.0.3... [ 1 of 67] Compiling Paths_Cabal ( dist/build/autogen/Paths_Cabal.hs, dist/build/Paths_Cabal.o ) <<< snip >>> [56 of 65] Compiling Distribution.Client.SetupWrapper ( Distribution/Client/SetupWrapper.hs, dist/build/cabal/cabal-tmp/Distribution/Client/SetupWrapper.o ) Distribution/Client/SetupWrapper.hs:51:12: Warning: In the use of `ghcVerbosityOptions' (imported from Distribution.Simple.GHC): Deprecated: "Use the GhcOptions record instead" [57 of 65] Compiling Distribution.Client.Upload ( Distribution/Client/Upload.hs, dist/build/cabal/cabal-tmp/Distribution/Client/Upload.o ) <<< snip >>> [65 of 65] Compiling Main ( Main.hs, dist/build/cabal/cabal-tmp/Main.o ) Linking dist/build/cabal/cabal ... Installing executable(s) in /home/cshome/o/ok/.cabal/bin /Developer/usr/bin/strip: object: /home/cshome/o/ok/.cabal/bin/cabal malformed object (unknown load command 15) cabal: Error: some packages failed to install: cabal-install-1.16.0.2 failed during the final install step. The exception was: ExitFailure 1 m% file ~/.cabal/bin/cabal /home/cshome/o/ok/.cabal/bin/cabal: Mach-O 64-bit executable x86_64 The strip(1) page ends with this, which may be relevant: LIMITATIONS Not every layout of a Mach-O file can be stripped by this program. But all layouts produced by the Apple compiler system can be stripped. m% otool -l ~/.cabal/bin/cabal <<< snip >>> Load command 14 cmd LC_FUNCTION_STARTS cmdsize 16 dataoff 12743064 datasize 204136 Load command 15 cmd ?(0x00000029) Unknown load command cmdsize 16 00c58f00 00000000 So something is definitely putting something in there that the Xcode 4.6.1 tools do not like.