from integer types to pointers and back. While we're at it, fix an older bug which might trigger if we ever have a platform where different pointer types have different sizes. Technically the standard does not guarantee (I think) that this isn't the case.
git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@9947 c06c8d41-db1a-0410-9941-cceddc491573
ZBSCKBHXQOLFNFEIMMHDCVQQR7JPLYMYUQXMYPQ7RBLAG4HT2QMAC