This issue addresses a similar problem as mentioned in #7706 but not to make the entire discussion to confusing and the fact that a similar problem was already solved there I created a new issue for this case.

When we have a number of source (.cpp) files with inside these files a similar / identical class definition we get the messages about:

error: md5 hash does not match for two different runs ...

It looks to me that the original filename is not taken into account in the file name of the image.
(tested with the current master 1.9.0 (0d8c2bb))

The following example contains a stripped down version of the source files but also the original files (.org): example.tar.gz

(The problem was seen in the clamav package on Fossies)

In the 1.8.15 version we don't get any messages but here references in the images point every time to the the same routine although it should be to a routine in a different file (so silently ignored). From 1.8.16 we get the warnings.