PC-lint organises detected issues into five categories of varying severity:
Conveniently, PC-lint has a -w option (usually included within the std.lnt indirect file or one of the warning policy files it references) which allows the PC-lint warning level (i.e. the minimum category of issues which will be detected) to be set globally. For example, -w3 (the default) will enable only messages of level "Warning" and above - so all Elective Notes and Informational Messages will be suppressed. Similarly, -w4 will enable all messages except Elective Notes.
If you need to enable a specific message below the current warning level, you can simply add a +e directive for the message in question after the -w option. This brings us to a very useful way of detecting only specific issues - for example, if you wanted to detect any unused include files in a project, adding the options -w0 +e766 to your command line (after all other .lnt files) will enable only message 766 ("Header file not used in module").
The following are examples of the sort of issues we specifically look for the first time we analyse a codebase (interestingly, very few of them are warnings – most are actually informational):
If you are running PC-lint on a codebase for the first time with a (consequently) relaxed warning policy, it may just be worth turning on any issues you are specifically concerned about (using a +e directive in options.lnt ) to see if any of them manifest themselves.