-xc, feature suggestion

[Frederik Eaton]

Hi,

I think it would be a good idea to print instructions for getting more
information when a program fails with a pattern match or other error.

Rather than

foo: Prelude.undefined

it should say

foo: Prelude.undefined
For information about the location of this error, recompile with "-prof -auto-all" and run with "+RTS -xc -RTS"

Also, maybe these instructions aren't enough? When I do the above, it
just prints

<GHC.Err.CAF><GHC.Err.CAF><GHC.Err.CAF><GHC.Err.CAF>foo: Prelude.undefined

which isn't what I was looking for... Am I forgetting an option or
something?

Thanks,

Frederik

-- 
http://ofb.net/~frederik/