EViews.com

If you ask for a histogram and stats for a series with zero variance you get a warning message but nothing else. Not really a bug, but why not just show the output?

The distribution graph histogram does display the graph with arbitrary bar width.

The simple statistics histogram view is presumably generating an error on the computation of some of the descriptive statistics because of the zero variance, and possibly in the computation of the bar widths. I'll make a note to see if we can handle the error gracefully, though I remain skeptical of the usefulness of the graph

Would it save effort to replace the graph with a note that says "No variance, hence no histogram?" (Seriously.)