We have non np 1.6 compatible code in the gdk backend which we do not test on travis.

Issue reported by @cgohlke

http://matplotlib.1069221.n5.nabble.com/Matplotlib-devel-First-release-candidate-for-the-1-5-0-series-tp46156p46166.html

http://stackoverflow.com/questions/28499580/matplotlib-import-error-backend-gdk-soundefined-symbol-pyarray-setbaseobjec

The code in question went in in
#3665

which was in response to discussion at

http://thread.gmane.org/gmane.comp.python.matplotlib.general/34771/focus=34771

Options here are:

• fix code to address both issues (no idea how hard that would be)
• up the minimal numpy until it works

I am in favor of bumping the numpy version, but do not feel strongly.