Spurious verification reports

[fpoli]

From time to time, I see that the Viper IDE reports more, or even less, errors that it should. In the former case, the extra errors seem to be on old versions of the program. In the latter case, it's even possible that the IDE reports the green message in the status bar, but repeating the verification actually shows that there are errors. In those cases, the state of the IDE was stable. Letting it wait for a few seconds did not change the (non)reported errors.

I think that this issue might be related to how the Viper IDE cancels verification requests. If I save the file of a program with errors while it's being verified, I sometimes see that in the status bar the Viper IDE flashes a green error message (because no errors were found in the canceled verification request) before replacing it with another message.