If "foo" is any non-mandatory lint category (for example, "serial") then a javac flag like "-Xlint:none,foo" is being handled incorrectly by the compiler.

Whereas "-Xlint:all,-foo" means "Enable all categories, then remove foo", the flag "-Xlint:none,foo" should mean "Disable all categories, then add foo".

However, the actual effect of "-Xlint:none,foo" is the same as "-Xlint:none", that is, "Disable all categories, period."

Reproducer:

    $ cat NoSUID.java
    class NoSUID implements java.io.Serializable { }
    $ javac -Xlint:all NoSUID.java
    NoSUID.java:1: warning: [serial] serializable class NoSUID has no definition of serialVersionUID
    class NoSUID implements java.io.Serializable { }
    ^
    1 warning
    $ javac -Xlint:all,-serial NoSUID.java
    $ javac -Xlint:none NoSUID.java
    $ javac -Xlint:none,serial NoSUID.java # MISSING WARNING HERE
    $ javac -Xlint:serial NoSUID.java
    NoSUID.java:1: warning: [serial] serializable class NoSUID has no definition of serialVersionUID
    class NoSUID implements java.io.Serializable { }
    ^
    1 warning
    $ javac -version
    javac 24