[Rd] R crashes when resizing windows (PR#2992)

[dmurdoch at pair.com]

On Tue, 13 May 2003 15:57:36 +0100, you wrote:

>I tried R-1.7.0 Patched too and the problem hasn't changed.

I can reproduce this, and I'm close to having a patch to put in for
it.  However, I'm finding lots of oddities in Graphapp; I'm not sure
which of them is to blame!

 - GETHDC is being passed a null object, and is trying to dereference
it.  This is likely the immediate cause of the crash.  But where is
that null object coming from?

 - The reference counting code will only decrease the reference count
if the count is exactly 1, but it will increase any positive count.
This is probably causing memory leaks.

 - There's an array that caches "device contexts".  It's being handled
in a very strange way.

Duncan Murdoch