weird compiler bug/failed to load interface

[Hal Daume III]

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There's one module I wrote that I use in a lot of my programs and for some
reason, whenever I compile a program using this module with -O or -O2,
make changes to the Main, and then recompile, I get the following error
from ghc:

Skipping  Pattern          ( Pattern.hs, Pattern.o )

failed to load interface for `Pattern':
    Could not find interface file for `Pattern'

Failed to find interface decl for `Pattern.a'
from module `Pattern'

if I "ls Pattern.*" I get Pattern.hi, Pattern.hs and Pattern.o.

In order to get it to compile correctly, I have to rm Pattern.o and then
rerun ghc on the Main module.

I've attached the Pattern.hs fyi.  If anyone has any suggestions, please
let me know.  (btw, I'm using --make)

Thanks!

 - Hal

--
Hal Daume III

 "Computer science is no more about computers    | hdaume@isi.edu
  than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume

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