packed_annotation
Structs must have at most one 'Packed' annotation.
Description
#The analyzer produces this diagnostic when a subclass of Struct
has more than one Packed
annotation.
For more information about FFI, see C interop using dart:ffi.
Example
#The following code produces this diagnostic because the class C
, which is a subclass of Struct
, has two Packed
annotations:
dart
import 'dart:ffi';
@Packed(1)
@Packed(1)
final class C extends Struct {
external Pointer<Uint8> notEmpty;
}
Common fixes
#Remove all but one of the annotations:
dart
import 'dart:ffi';
@Packed(1)
final class C extends Struct {
external Pointer<Uint8> notEmpty;
}
Unless stated otherwise, the documentation on this site reflects Dart 3.7.3. Page last updated on 2025-05-08. View source or report an issue.