no_annotation_constructor_arguments

Annotation creation must have arguments.

The analyzer produces this diagnostic when an annotation is the name of a class, such as @C, or of a constructor, such as @C.named, rather than the name of a variable. To create an instance of the class, the name must be followed by an argument list. This diagnostic is reported whether or not the constructor is a const constructor.

The following code produces this diagnostic because C is a class, and a class can't be used as an annotation without invoking a const constructor from the class:

class C {
  const C();
}
​
@C
var x = 0;

Add the missing argument list:

class C {
  const C();
}
​
@C()
var x = 0;