What does "Skipping analysis for function at" mean?

[psifertex]

See subject.

[psifertex]

This is a question we occasionally get via support that I wanted to put together a longer response in one place for. First, what does that specific message me? The short explanation is that to prevent very slow analysis we have a few filters that can prevent a function from being analyzed. This could be because the function is too big, because analysis has looped too many times, because analysis is taking too long, or a lookup table is too big. Using the settings described at each of those links you can actually see what hte defaults are and change them as appropriate for your binary.

That said, sometimes those warnings (especially the analysis loop limit one) are indicative of some spot where Binary Ninja's analysis could be improved. If that's the case and you can share your binary, please file an issue.

If you can't share your binary though and just want to disable the warnings, you've got a few options.

First, you can disable the analysis for a particular function via the right-click menu or the api (current_function.analysis_skipped = True as one example).

Next, you can change the default logging levels. (Note that there are distinct settings for headless operation via python and via the UI itself)

Of course, if you are seeing many similar warnings this may also be a sign that Binary Ninja is attempting to analyze garbage functions that shouldn't be functions at all. In this case, it's useful to examine the format of the file you're analyzing. If you feed in a giant firmware file and simply let linear sweep run, you'll undoubtably be analyzing many pieces of data that aren't actually code and they are likely to cause errors like this. Given that, sometimes it's as simply as creating or changing a section with appropriate semantics which will prevent creation of functions in known code-locations.