Here's a less trivial file with a very similar-looking bug to the last one. In this case, the bug is $ jhc -dc -D_JHC_STANDALONE=0 -o test.ko test.hs jhc -dc -D_JHC_STANDALONE=0 -o test.ko test.hs jhc 0.7.3 (0.7.2-30) Finding Dependencies... Using Ho Cache: '/mnt/home/droundy/.jhc/cache' test.hs:1 - Warning: The pragma 'LANGUAGE' is unknown Main [test.hs] Typechecking... [1 of 1] Main (.............................................) Compiling... [1 of 1] Main user error (specializeE: attempt to specialize types that do not unify: (Jhc@.Absurd.^** (), Jhc.Prim.IO ()) ELit (Jhc@.Absurd.^** (ELit (Jhc.Basics.()::ESort *))::ESort *) ELit (Jhc.Prim.IO (ELit (Jhc.Basics.()::ESort *))::ESort *)) and once again, it disappears when I add the type signature back in. David On Sun, Sep 13, 2009 at 7:14 PM, David Roundy wrote:

Here's another bug,

Compiling the attached file, I get

$ jhc test.hs jhc test.hs jhc 0.7.3 (0.7.2-30) Finding Dependencies... Using Ho Cache: '/mnt/home/droundy/.jhc/cache' Main                    [test.hs] Typechecking... [1 of 1] Main             (.............................................) Compiling... [1 of 1] Main             <..................................................> src/FrontEnd/Representation.hs:98:0: No instance nor default method for class operation Data.Binary.put

If I uncomment the type signature for main, the file compiles.  It's not an important sort of program, but a compiler bug is a compiler bug, and I imagine it might manifest itself in some non-trivial program. -- David Roundy

-- David Roundy