diff --git a/pkgs/ffigen/lib/src/code_generator/compound.dart b/pkgs/ffigen/lib/src/code_generator/compound.dart
index 55bc5691a3..00fb2f45f5 100644
--- a/pkgs/ffigen/lib/src/code_generator/compound.dart
+++ b/pkgs/ffigen/lib/src/code_generator/compound.dart
@@ -5,6 +5,7 @@
 import '../code_generator.dart';
 import '../config_provider.dart';
 import '../context.dart';
+import '../header_parser/sub_parsers/api_availability.dart';
 import '../visitor/ast.dart';
 
 import 'binding_string.dart';
@@ -58,6 +59,15 @@ abstract class Compound extends BindingType with HasLocalScope {
     return type.getCType(context);
   }
 
+  @override
+  ApiAvailability get computeAvailability {
+    var avail = ApiAvailability.alwaysAvailable;
+    for (final member in members) {
+      avail = avail.merge(member.type.computeAvailability);
+    }
+    return avail;
+  }
+
   @override
   bool get isObjCImport =>
       context.objCBuiltInFunctions.getBuiltInCompoundName(originalName) != null;
diff --git a/pkgs/ffigen/lib/src/code_generator/func_type.dart b/pkgs/ffigen/lib/src/code_generator/func_type.dart
index 1f818965bd..d71f84885c 100644
--- a/pkgs/ffigen/lib/src/code_generator/func_type.dart
+++ b/pkgs/ffigen/lib/src/code_generator/func_type.dart
@@ -4,6 +4,7 @@
 
 import '../code_generator.dart';
 import '../context.dart';
+import '../header_parser/sub_parsers/api_availability.dart';
 import '../visitor/ast.dart';
 import 'scope.dart';
 
@@ -60,6 +61,18 @@ class FunctionType extends Type with HasLocalScope {
     return sb.toString();
   }
 
+  @override
+  ApiAvailability get computeAvailability {
+    var avail = returnType.computeAvailability;
+    for (final param in parameters) {
+      avail = avail.merge(param.type.computeAvailability);
+    }
+    for (final param in varArgParameters) {
+      avail = avail.merge(param.type.computeAvailability);
+    }
+    return avail;
+  }
+
   @override
   String getCType(Context context, {bool writeArgumentNames = true}) =>
       _getTypeImpl(
@@ -159,6 +172,9 @@ class NativeFunc extends Type {
     return _type as FunctionType;
   }
 
+  @override
+  ApiAvailability get computeAvailability => type.computeAvailability;
+
   @override
   String getCType(Context context, {bool writeArgumentNames = true}) {
     final funcType = _type is FunctionType
diff --git a/pkgs/ffigen/lib/src/code_generator/objc_block.dart b/pkgs/ffigen/lib/src/code_generator/objc_block.dart
index da7d4b3940..ebc9519c82 100644
--- a/pkgs/ffigen/lib/src/code_generator/objc_block.dart
+++ b/pkgs/ffigen/lib/src/code_generator/objc_block.dart
@@ -4,6 +4,7 @@
 
 import '../code_generator.dart';
 import '../context.dart';
+import '../header_parser/sub_parsers/api_availability.dart';
 import '../strings.dart' as strings;
 import '../visitor/ast.dart';
 
@@ -149,6 +150,15 @@ class ObjCBlock extends BindingType with HasLocalScope {
 
   bool get hasListener => returnType == voidType;
 
+  @override
+  ApiAvailability get computeAvailability {
+    var avail = returnType.computeAvailability;
+    for (final param in params) {
+      avail = avail.merge(param.type.computeAvailability);
+    }
+    return avail;
+  }
+
   String _blockType(Context context) {
     final argStr = params
         .map((param) {
@@ -444,10 +454,13 @@ ref.pointer.ref.invoke.cast<${_helper.trampNatFnCType}>()
       context.rootObjCScope.addPrivate('_BlockingTrampoline'),
     );
 
+    final availStr = computeAvailability.apiAvailableMacro;
+    final avail = availStr == null ? '' : '$availStr\n';
+
     return '''
 
-typedef ${returnType.getNativeType()} (^$listenerName)($declArgStr);
-__attribute__((visibility("default"))) __attribute__((used))
+${avail}typedef ${returnType.getNativeType()} (^$listenerName)($declArgStr);
+${avail}__attribute__((visibility("default"))) __attribute__((used))
 $listenerName $listenerWrapper($listenerName block) NS_RETURNS_RETAINED {
   return ^void($argStr) {
     ${generateRetain('block')};
@@ -455,8 +468,8 @@ $listenerName $listenerWrapper($listenerName block) NS_RETURNS_RETAINED {
   };
 }
 
-typedef ${returnType.getNativeType()} (^$blockingName)($blockingArgStr);
-__attribute__((visibility("default"))) __attribute__((used))
+${avail}typedef ${returnType.getNativeType()} (^$blockingName)($blockingArgStr);
+${avail}__attribute__((visibility("default"))) __attribute__((used))
 $listenerName $blockingWrapper(
     $blockingName block, $blockingName listenerBlock,
     DOBJC_Context* ctx) NS_RETURNS_RETAINED {
@@ -495,10 +508,13 @@ $listenerName $blockingWrapper(
     final getterSel = '@selector(getDOBJCDartProtocolMethodForSelector:)';
     final blkGetter = '(($block)$msgSend(target, $getterSel, sel))';
 
+    final availStr = computeAvailability.apiAvailableMacro;
+    final avail = availStr == null ? '' : '$availStr\n';
+
     return '''
 
-typedef $ret (^$block)($argRecv);
-__attribute__((visibility("default"))) __attribute__((used))
+${avail}typedef $ret (^$block)($argRecv);
+${avail}__attribute__((visibility("default"))) __attribute__((used))
 $ret $fnName(id target, $argRecv) {
   return $blkGetter($argPass);
 }
diff --git a/pkgs/ffigen/lib/src/code_generator/objc_interface.dart b/pkgs/ffigen/lib/src/code_generator/objc_interface.dart
index 32bb152fac..b18a23f708 100644
--- a/pkgs/ffigen/lib/src/code_generator/objc_interface.dart
+++ b/pkgs/ffigen/lib/src/code_generator/objc_interface.dart
@@ -76,6 +76,9 @@ class ObjCInterface extends BindingType with ObjCMethods, HasLocalScope {
 
   bool get unavailable => apiAvailability.availability == Availability.none;
 
+  @override
+  ApiAvailability get computeAvailability => apiAvailability;
+
   @override
   BindingString toBindingString(Writer w) {
     final context = w.context;
diff --git a/pkgs/ffigen/lib/src/code_generator/objc_protocol.dart b/pkgs/ffigen/lib/src/code_generator/objc_protocol.dart
index 66f9d1c39f..ebe14f4e35 100644
--- a/pkgs/ffigen/lib/src/code_generator/objc_protocol.dart
+++ b/pkgs/ffigen/lib/src/code_generator/objc_protocol.dart
@@ -65,6 +65,9 @@ class ObjCProtocol extends BindingType with ObjCMethods, HasLocalScope {
 
   bool get unavailable => apiAvailability.availability == Availability.none;
 
+  @override
+  ApiAvailability get computeAvailability => apiAvailability;
+
   @override
   BindingString toBindingString(Writer w) {
     final protocolClass = ObjCBuiltInFunctions.protocolClass.gen(context);
diff --git a/pkgs/ffigen/lib/src/code_generator/pointer.dart b/pkgs/ffigen/lib/src/code_generator/pointer.dart
index aeb4f77405..fff39356c5 100644
--- a/pkgs/ffigen/lib/src/code_generator/pointer.dart
+++ b/pkgs/ffigen/lib/src/code_generator/pointer.dart
@@ -4,6 +4,7 @@
 
 import '../code_generator.dart';
 import '../context.dart';
+import '../header_parser/sub_parsers/api_availability.dart';
 import '../visitor/ast.dart';
 
 /// Represents a pointer.
@@ -21,6 +22,9 @@ class PointerType extends Type {
     return PointerType._(child);
   }
 
+  @override
+  ApiAvailability get computeAvailability => child.computeAvailability;
+
   @override
   Type get baseType => child.baseType;
 
diff --git a/pkgs/ffigen/lib/src/code_generator/type.dart b/pkgs/ffigen/lib/src/code_generator/type.dart
index c269099b92..4191ae0448 100644
--- a/pkgs/ffigen/lib/src/code_generator/type.dart
+++ b/pkgs/ffigen/lib/src/code_generator/type.dart
@@ -4,6 +4,7 @@
 
 import '../code_generator.dart';
 import '../context.dart';
+import '../header_parser/sub_parsers/api_availability.dart';
 import '../visitor/ast.dart';
 import 'scope.dart';
 
@@ -132,6 +133,9 @@ abstract class Type extends AstNode {
   /// that default values aren't supported for this type, eg void.
   String? getDefaultValue(Context context) => null;
 
+  /// Returns the availability of this type and all its nested types.
+  ApiAvailability get computeAvailability => ApiAvailability.alwaysAvailable;
+
   @override
   void visit(Visitation visitation) => visitation.visitType(this);
 
@@ -242,6 +246,9 @@ abstract class BindingType extends NoLookUpBinding implements Type {
   @override
   bool get isObjCImport => false;
 
+  @override
+  ApiAvailability get computeAvailability => ApiAvailability.alwaysAvailable;
+
   @override
   void visit(Visitation visitation) => visitation.visitBindingType(this);
 }
diff --git a/pkgs/ffigen/lib/src/code_generator/typealias.dart b/pkgs/ffigen/lib/src/code_generator/typealias.dart
index 3bf9182fd4..07e2eb77de 100644
--- a/pkgs/ffigen/lib/src/code_generator/typealias.dart
+++ b/pkgs/ffigen/lib/src/code_generator/typealias.dart
@@ -4,6 +4,7 @@
 
 import '../code_generator.dart';
 import '../context.dart';
+import '../header_parser/sub_parsers/api_availability.dart';
 import '../strings.dart' as strings;
 import '../visitor/ast.dart';
 import 'binding_string.dart';
@@ -105,6 +106,9 @@ class Typealias extends BindingType {
     return pointee.type;
   }
 
+  @override
+  ApiAvailability get computeAvailability => type.computeAvailability;
+
   @override
   BindingString toBindingString(Writer w) {
     assert(!isAnonymous);
diff --git a/pkgs/ffigen/lib/src/header_parser/sub_parsers/api_availability.dart b/pkgs/ffigen/lib/src/header_parser/sub_parsers/api_availability.dart
index a5cdde0d78..e1f2db592c 100644
--- a/pkgs/ffigen/lib/src/header_parser/sub_parsers/api_availability.dart
+++ b/pkgs/ffigen/lib/src/header_parser/sub_parsers/api_availability.dart
@@ -21,14 +21,17 @@ class ApiAvailability {
   final PlatformAvailability? macos;
 
   late final Availability availability;
+  final ExternalVersions? _externalVersions;
+
+  static final alwaysAvailable = ApiAvailability(externalVersions: null);
 
   ApiAvailability({
     this.alwaysDeprecated = false,
     this.alwaysUnavailable = false,
     this.ios,
     this.macos,
-    required ExternalVersions? externalVersions,
-  }) {
+    ExternalVersions? externalVersions,
+  }) : _externalVersions = externalVersions {
     availability = _getAvailability(externalVersions);
   }
 
@@ -152,6 +155,57 @@ class ApiAvailability {
     return "$checkOsVersion('$apiName', $args);";
   }
 
+  ApiAvailability merge(ApiAvailability other) {
+    if (this == alwaysAvailable) return other;
+    if (other == alwaysAvailable) return this;
+
+    return ApiAvailability(
+      alwaysDeprecated: alwaysDeprecated || other.alwaysDeprecated,
+      alwaysUnavailable: alwaysUnavailable || other.alwaysUnavailable,
+      ios: PlatformAvailability.merge(ios, other.ios),
+      macos: PlatformAvailability.merge(macos, other.macos),
+      externalVersions: _externalVersions ?? other._externalVersions,
+    );
+  }
+
+  String? get apiAvailableMacro {
+    if (alwaysUnavailable) return '__attribute__((unavailable))';
+    if (alwaysDeprecated) return '__attribute__((deprecated))';
+
+    final platforms = _platforms;
+    if (platforms.isEmpty) return null;
+
+    final attributes = <String>[];
+    for (final platform in platforms) {
+      if (platform.unavailable) {
+        attributes.add(
+          'availability(${platform.name!.toLowerCase()}, unavailable)',
+        );
+      } else {
+        final platformAttrs = <String>[];
+        if (platform.introduced != null) {
+          platformAttrs.add('introduced=${platform.introduced}');
+        }
+        if (platform.deprecated != null) {
+          platformAttrs.add('deprecated=${platform.deprecated}');
+        }
+        if (platform.obsoleted != null) {
+          platformAttrs.add('obsoleted=${platform.obsoleted}');
+        }
+        if (platformAttrs.isNotEmpty) {
+          attributes.add(
+            // ignore: lines_longer_than_80_chars
+            'availability(${platform.name!.toLowerCase()},${platformAttrs.join(',')})',
+          );
+        } else {
+          attributes.add('availability(${platform.name!.toLowerCase()})');
+        }
+      }
+    }
+    if (attributes.isEmpty) return null;
+    return attributes.map((a) => '__attribute__(($a))').join(' ');
+  }
+
   @override
   String toString() =>
       '''Availability {
@@ -185,6 +239,53 @@ class PlatformAvailability {
     return deprecated! < obsoleted! ? deprecated : obsoleted;
   }
 
+  static PlatformAvailability? merge(
+    PlatformAvailability? a,
+    PlatformAvailability? b,
+  ) {
+    if (a == null) return b;
+    if (b == null) return a;
+
+    Version? newIntroduced;
+    if (a.introduced == null) {
+      newIntroduced = b.introduced;
+    } else if (b.introduced == null) {
+      newIntroduced = a.introduced;
+    } else {
+      newIntroduced = a.introduced! > b.introduced!
+          ? a.introduced
+          : b.introduced;
+    }
+
+    Version? newDeprecated;
+    if (a.deprecated == null) {
+      newDeprecated = b.deprecated;
+    } else if (b.deprecated == null) {
+      newDeprecated = a.deprecated;
+    } else {
+      newDeprecated = a.deprecated! < b.deprecated!
+          ? a.deprecated
+          : b.deprecated;
+    }
+
+    Version? newObsoleted;
+    if (a.obsoleted == null) {
+      newObsoleted = b.obsoleted;
+    } else if (b.obsoleted == null) {
+      newObsoleted = a.obsoleted;
+    } else {
+      newObsoleted = a.obsoleted! < b.obsoleted! ? a.obsoleted : b.obsoleted;
+    }
+
+    return PlatformAvailability(
+      name: a.name ?? b.name,
+      introduced: newIntroduced,
+      deprecated: newDeprecated,
+      obsoleted: newObsoleted,
+      unavailable: a.unavailable || b.unavailable,
+    );
+  }
+
   @visibleForTesting
   Availability getAvailability(Versions version) {
     if (unavailable) {