Hi, I am trying to install Criterion package, but I keep getting an error and I can't figure it out why it is like this !! mozhgan@Mozhgan-KCh:~$ cabal install Criterion Resolving dependencies... Configuring vector-algorithms-0.3... Preprocessing library vector-algorithms-0.3... Building vector-algorithms-0.3... [1 of 9] Compiling Data.Vector.Algorithms.Common ( Data/Vector/Algorithms/Common.hs, dist/build/Data/Vector/Algorithms/Common.o ) [2 of 9] Compiling Data.Vector.Algorithms.Search ( Data/Vector/Algorithms/Search.hs, dist/build/Data/Vector/Algorithms/Search.o ) [3 of 9] Compiling Data.Vector.Algorithms.Radix ( Data/Vector/Algorithms/Radix.hs, dist/build/Data/Vector/Algorithms/Radix.o ) [4 of 9] Compiling Data.Vector.Algorithms.Optimal ( Data/Vector/Algorithms/Optimal.hs, dist/build/Data/Vector/Algorithms/Optimal.o ) [5 of 9] Compiling Data.Vector.Algorithms.Insertion ( Data/Vector/Algorithms/Insertion.hs, dist/build/Data/Vector/Algorithms/Insertion.o ) [6 of 9] Compiling Data.Vector.Algorithms.Merge ( Data/Vector/Algorithms/Merge.hs, dist/build/Data/Vector/Algorithms/Merge.o ) [7 of 9] Compiling Data.Vector.Algorithms.TriHeap ( Data/Vector/Algorithms/TriHeap.hs, dist/build/Data/Vector/Algorithms/TriHeap.o ) [8 of 9] Compiling Data.Vector.Algorithms.Intro ( Data/Vector/Algorithms/Intro.hs, dist/build/Data/Vector/Algorithms/Intro.o ) ghc: panic! (the 'impossible' happened) (GHC version 6.10.4 for i386-unknown-linux): idInfo co{v a9WB} [tv] Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug cabal: Error: some packages failed to install: criterion-0.5.0.0 depends on vector-algorithms-0.3 which failed to install. statistics-0.5.1.0 depends on vector-algorithms-0.3 which failed to install. vector-algorithms-0.3 failed during the building phase. The exception was: exit: ExitFailure 1 I tried to install Statistics and vector-algorithms package separately before installing the Criterion package itself .. but it wasn't successful. Thanks, Mozhgan