There are two regressions found on previous security updates: mariadb and pidgin. MariaDB developers made some changes in one of their headers, my_config.h that caused some problems with other packages that are linked against it.
I first spotted this problem when trying to compile gdal on SlackBuilds repository. I reported this to the maintainer and soon after, we both found that it's not just gdal that were broken, but many others, namely php, apr-utils, mysql-workbench, etc. I googled a bit and found a patch in other project, so i tried to apply it on my own computer and it worked, so i proposed the patch to Patrick and got accepted.
Second regression was on pidgin. Upstream developers broke Gadu-Gadu protocol when providing security update. Mancha found a patch to fix the problem and got accepted as well.
In -current, firefox has been upgraded to 33.1 as well.