Odd FFI behavior

[Donn Cave]

...
> Because the failures are not general in that they target one
> particular value, and seem to be affected by time, it makes me
> wonder if there is some subtle Haskell run time issue. Like,
> could the garbage collector be interacting with things?
> 
> Does anyone have an idea what kind of things to look for?

Sure - not that I have worked out in any detail how this would
do what you're seeing, but it's easy to do and often enough
works.

Compile with RTS options enabled and invoke with RTS option -V0.

That will disable the runtime internal timer, which uses signals.
The flood of signals from this source can interrupt functions
that aren't really designed to deal with that, because in a more
normal context they don't have to.

	Donn