Have you read the documentation of the cover tool?

You don't show how exactly you are invoking the cover tool to "sometimes" get the error (or warning) message. I guess that, as the message says, there are multiple interpretations for the given option of -report and the tool does not know which one you meant.

I guess you need to be more explicit in your choice of options.

In reply to Re: devel cover ambigous error by Corion
in thread devel cover ambigous error by david2008

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