annotation_ on_ pointer_ field
Fields in a struct class whose type is 'Pointer' shouldn't have any annotations.
Description
#
The analyzer produces this diagnostic when a field that's declared in a
subclass of Struct and has the type Pointer also has an annotation
associated with it.
For more information about FFI, see C interop using dart:ffi.
Example
#
The following code produces this diagnostic because the field p, which
has the type Pointer and is declared in a subclass of Struct, has the
annotation @Double():
import 'dart:ffi';
final class C extends Struct {
@Double()
external Pointer<Int8> p;
}
Common fixes
#Remove the annotations from the field:
import 'dart:ffi';
final class C extends Struct {
external Pointer<Int8> p;
}
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Page last updated on 2025-9-4. View source or report an issue.