I am posting this to the mailing list, but it is a copy of a post I originally made on Haskell Reddit. http://www.reddit.com/r/haskell/comments/22wu92/problems_installing_ghc_782_... My GHC is working fine now. But there seem to be some changes in either GHC 7.8.2 or Cabal-1.18.1.3 that have broken some of the older packages in Hackage. *TL;DR* I discovered the "Crypto-4.2.5.1 package is broken, and trying to install "terminfo-0.4.0.0" breaks GHC by over-writing the terminfo library that came with the GHC tarball because isn't in the GHC package registry. I downloaded the binary distribution from here: https://www.haskell.org/ghc/dist/7.8.2/ghc-7.8.2-x86_64-unknown-linux-deb7.t... and then immediately began re-building all of the packages in my .cabal/packages/hackage.haskell.org/ direcotry. I admit, all of my problems may be due to my Cabal config, but I haven't had any problems with it before this, as far as I know it is the default setup the option to build profiling libraries set to True. The first problem I had was that Crypto-2.5.4.1 was not building files correctly. *Some* of shared object files "*.dyn_o" were being built *without* their accompanying "*.dyn_hi" files, although some of the "*.dyn_hi" files did exist). When cabal tried to copy these "*.dyn_hi" files to the global package registry during installation it would fail with something about (for example) "could not find RSA.dyn_hi". To solve this, I rebuilt every "*.dyn_o" file that did not have an accompanying "*.dyn_hi" by hand using the command ghc -dynamic --make Codec.Binary.RSA The resulting "Codec/Binary/RSA.hi" file was actually a dynamic interface file but it's file extension was just ".hi" for some reason, (I double checked by using ghc --show-iface) so I just copied it it the "dist/build/Codec/Binary/" directory. I did this for every "*.hi" file that was supposed to be named "*.dyn_hi". This included about 10 files. Again, some "*.dyn_o" did build correctly with an accompanying "*.dyn_hi", about 10 of the modules were built incorrectly, all the rest were OK. The second problem I had was with installing "Yi" which relies on the "terminfo-0.4.0.0" package. The "terminfo" library that came with the GHC 7.8.2 binary distribution does not show up in the output of "ghc-pkg list", so Cabal tries to build it thinking it doesn't exist, and it overwrites the existing "terminfo-0.4.0.0" package with a library that contains missing symbols. This causes GHC to completely stop working. The "ghc" program immediately fails with an error: symbol lookup error: /usr/local/lib/ghc-7.8.2/bin/../haskeline-0.7.1.2/libHShaskeline-0.7.1.2-ghc7.8.2.so: \ undefined symbol: terminfozm0zi4zi0zi0_SystemziConsoleziTerminfoziCursor_moveDown5_info I was able to solve this problem by simply copying the contents of: ghc-7.8.2/libraries/terminfo/dist-install/build/* from the source distribution tarball to the GHC installation directory: /usr/local/lib/ghc-7.8.2/terminfo-0.4.0.0/ and that solved the problem. But any program depending on "terminfo" simply will not install properly. The terminfo-0.4.0.0 package does not show up in the output of ghc-pkg list, even though it comes with the GHC 7.8.2 tarball and GHC relies on it. Attempting to install Terminfo will build a ".so" file that GHC cannot use. *So don't install terminfo-0.4.0.0 from Hackage.* Fortunately, Yi is not something that is absolutely necessary. I was able to install every other package I needed (lens, diagrams, yesod, xmonad, gtk) without incident. But whatever changes have been made in ghc-7.8.2 and the accompanying Cabal-1.18.1.3 seem to have broken some of the older Hackage packages.