unexpected space leak

Julian Seward (Intl Vendor) v-julsew@microsoft.com
Thu, 20 Dec 2001 02:10:37 -0800

It's a hack we put in, because fixing the bytecode generator=20
properly for this relatively obscure case was a lot of effort
and other calls on our time (we were stabilising for the 5.02
release at the time) were more pressing.

It is (nearly) harmless.

What usually causes it is having strict polymorphic fields
on constructors:

   data T a =3D T !a

The warning is intended to mean that the strictness annotation
will be ignored in interpreted code.  This shouldn't have any
effect on the overall outcome of your program, unless it depends
on evaluation order changes induced by the !, for some gruesome
reason.  However, the space behaviour may well be different from
what it would be if ! was observed.

If you do experience problems as a result of this, I'd be=20
interested to hear of them.


| -----Original Message-----
| From: Hal Daume III [mailto:hdaume@ISI.EDU]=20
| Sent: Wednesday, December 19, 2001 11:22 PM
| To: GHC Users Mailing List
| Subject: unexpected space leak
| what does it mean when ghci says:
| WARNING: ignoring polymorphic case in interpreted mode.
|    Possibly due to strict polymorphic/functional constructor args.
|    Your program may leak space unexpectedly.
| --
| Hal Daume III
|  "Computer science is no more about computers    | hdaume@isi.edu
|   than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume
| _______________________________________________
| Glasgow-haskell-users mailing list
| Glasgow-haskell-users@haskell.org
| http://www.haskell.org/mailman/listinfo/glasgow-haskell-users