address_receiver

The receiver of '.address' must be a concrete 'TypedData', a concrete 'TypedData' '[]', an 'Array', an 'Array' '[]', a Struct field, or a Union field.

The analyzer produces this diagnostic when the .address getter is used on a receiver whose static type isn't one of the allowed FFI types. The .address getter is used to obtain a Pointer to the underlying memory of an FFI data structure.

The receiver of .address must be one of the following:

• A concrete TypedData instance (e.g., Uint8List).
• An element of a concrete TypedData instance accessed via [].
• An Array<T> instance (from dart:ffi).
• An element of an Array<T> instance accessed via [].
• A field of a Struct or Union subclass, if that field's type is Array<T>, a nested Struct, or a nested Union.
• A Struct or Union instance.

The following code produces this diagnostic for various incorrect receivers:

import 'dart:ffi';

final class MyStruct extends Struct {
  @Uint8()
  external int x;

  @Uint8()
  external int y;
}

@Native<Void Function(Pointer)>(isLeaf: true)
external void nativeLeafCall(Pointer ptr);

void main() {
  final struct = Struct.create<MyStruct>();
  final y = struct.y;
  // Incorrect: The receiver is not a struct field, but some integer.
  nativeLeafCall(y.address);
}

Ensure that the receiver of the .address getter is one of the allowed types. The .address getter is for obtaining a Pointer to the memory of TypedData, Array, Struct, or Union instances, or certain fields/elements thereof.

import 'dart:ffi';

@Native<Void Function(Pointer)>(isLeaf: true)
external void nativeLeafCall(Pointer ptr);

final class MyStruct extends Struct {
  @Uint8()
  external int x;

  @Uint8()
  external int y;
}

void main() {
  final struct = Struct.create<MyStruct>();
  // Correct: The receiver is a struct field.
  nativeLeafCall(struct.y.address);
}