https://bugs.winehq.org/show_bug.cgi?id=51985
--- Comment #1 from Nikolay Sivov bunglehead@gmail.com --- We have such categories already: trace, fixme, warn, err. Whether it's fatal or not depends on context. Calls to unimplemented functions or asserts will already print distinct messages.
It's not always possible to tell what went wrong from the log alone.
In your example, you're not running with vanilla wine to begin with. Is it wine-staging or some other build?