numpy/numpy — pull request #2747 by mdboom (2012-11-15 18:50:27+00:00)
Title: cannot access masked array rows with np.object dtype (Fixes #2432)

In the astropy project we've run into bug #2432. (See https://github.com/astropy/astropy/issues/465).

This bug is made more prominent the recent commit 7caac2efd9b2, since `mvoid` arrays are created in all cases, not just when there are masked elements.

The fix here is just to use the Numpy array constructor instead of itemwise assignment, which does handle object fields correctly.

Hope this makes sense -- I can't say I'm an expert on the masked array code.