[Haskell-cafe] Unrecognized function symbols in .prof

Iavor Diatchki iavor.diatchki at gmail.com
Tue Feb 8 08:45:58 CET 2011

Hi Lee,
I would also guess that these are probably the implementations of equality
in the given modules.

One way to test this would be to name the equality function explicitly.  For
example, something like this:

myEquality x y = ...
instance Eq MyType where (==) = myEquality

Another option would be to look at the generated core by using -ddump-simpl
when compiling. This will generate a whole bunch of output, which you can
redirect to a file and the search for the mysterious symbols inside.

Hope this helps,

On Mon, Feb 7, 2011 at 11:12 PM, Lee Pike <leepike at gmail.com> wrote:

> Hi,
> I am profiling a Haskell program using GHC, and after executing the
> program with +RTS -p, I get a .prof file that lists the cost centers
> of the program.  Some of the cost centers listed are for function
> symbols that do not exist in the given module.  For example, I have in
> my .prof file:
> COST CENTRE              MODULE   %time %alloc
> ==_a2MT                        Foo           19.8    0.0
> ==_a2R8                         Foo           17.8    0.0
> ==_a2Bg                         Bar           13.7    0.0
>                  ....                     ....
> It appears these are generated symbols; how do I find out what those
> function symbols correspond to?  (In this case, my assumption is that
> these symbols refer to instances of the Eq class, but I'm not sure.)
> [I couldn't find anything about this in the GHC online documentation
> or via Googling, but sorry if I missed it.]
> Thanks,
> Lee
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://www.haskell.org/mailman/listinfo/haskell-cafe
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20110207/46a41bc8/attachment.htm>

More information about the Haskell-Cafe mailing list