Upgrade may happen out of order?

[UnitedMarsupials-zz]

I was doing a portupgrade -a -rR today and noticed, that my PHP application (running under php-fpm) broke for a while:

PHP Startup: Unable to load dynamic library '/opt/lib/php/20151012-zts/gd.so' - Shared object "libpthread-stubs.so.0" not found, required by "libxcb.so.1" in Unknown on line 0

After the portupgrade run got to updating libxcb itself, things started to work again. But it probably should've done it before deleting the libpthread-stubs.so.0 (which used to be a link to libpthread-stubs.so.0.0.0). Maybe, this is related to #66 -- not sure...