The Revenge of Finalizers

Alastair Reid alastair at
Fri Oct 18 11:02:04 EDT 2002

> I can get it to fail another way too:

>   main = do
>     p <- mallocBytes 64
>     newForeignPtr p (print x)
>     print x
>    where
>     x = sum [1..10000]

The problem is probably this shared mutable variable used behind the
scenes in the implementation of the numeric show code (hugs98/src/printer.c)

  static Cell out;	/* GC'd var used by printer code   */

[It's also used if you use the -u flag to use Hugs' builtin printer
instead of the Show function - but I don't think anyone does that
anymore and we could probably kill that code without anyone noticing
(???).  (Unless, does Hood or some such use it?)]

I think all the functions affected return void so it'd be easy to
replace the global variable with a local which is threaded through
that set of functions.


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