diff --git a/runtime/tests/vm/dart/isolates/dart_api_create_lightweight_isolate_test.dart b/runtime/tests/vm/dart/isolates/dart_api_create_lightweight_isolate_test.dart
index f2e8a709bece..25e0199eb00e 100644
--- a/runtime/tests/vm/dart/isolates/dart_api_create_lightweight_isolate_test.dart
+++ b/runtime/tests/vm/dart/isolates/dart_api_create_lightweight_isolate_test.dart
@@ -14,6 +14,7 @@ import 'dart:isolate';
 import 'package:expect/expect.dart';
 import 'package:ffi/ffi.dart';
 
+import '../../../../../tests/ffi/calloc.dart';
 import '../../../../../tests/ffi/dylib_utils.dart';
 
 final bool isAOT = Platform.executable.contains('dart_precompiled_runtime');
@@ -62,7 +63,7 @@ abstract class FfiBindings {
       Expect.isTrue(isolate.address != 0);
       return isolate;
     } finally {
-      free(cname);
+      calloc.free(cname);
     }
   }
 
@@ -86,8 +87,8 @@ abstract class FfiBindings {
         onError != null ? onError.nativePort : 0,
         onExit != null ? onExit.nativePort : 0);
 
-    free(libraryUri);
-    free(functionName);
+    calloc.free(libraryUri);
+    calloc.free(functionName);
   }
 }
 
@@ -120,7 +121,7 @@ Future withPeerPointer(fun(Pointer<Void> peer)) async {
     // wait a little here to ensure the write of the callback has arrived.
     await Future.delayed(const Duration(milliseconds: 100));
     Expect.equals('xbz', Utf8.fromUtf8(peer.cast()));
-    free(peer);
+    calloc.free(peer);
   }
 }
 
diff --git a/runtime/tests/vm/dart/regress_41971_test.dart b/runtime/tests/vm/dart/regress_41971_test.dart
index 28f63ad1d5e9..7979d0d1e592 100644
--- a/runtime/tests/vm/dart/regress_41971_test.dart
+++ b/runtime/tests/vm/dart/regress_41971_test.dart
@@ -11,6 +11,8 @@ import 'dart:ffi';
 import 'package:expect/expect.dart';
 import 'package:ffi/ffi.dart';
 
+import '../../../../tests/ffi/calloc.dart';
+
 class X {
   int field;
   X(this.field);
@@ -35,8 +37,8 @@ int loadFrom(Pointer<Int32> p) {
 }
 
 void main() {
-  final p = allocate<Int32>(count: 128);
+  final p = calloc<Int32>(128);
   p[0] = 42;
   Expect.equals(42, loadFrom(p));
-  free(p);
+  calloc.free(p);
 }
diff --git a/runtime/tests/vm/dart/thread_priority_macos_test.dart b/runtime/tests/vm/dart/thread_priority_macos_test.dart
index b7c8280362f5..473c1ce267c0 100644
--- a/runtime/tests/vm/dart/thread_priority_macos_test.dart
+++ b/runtime/tests/vm/dart/thread_priority_macos_test.dart
@@ -10,6 +10,8 @@ import 'dart:io';
 import 'package:expect/expect.dart';
 import 'package:ffi/ffi.dart';
 
+import '../../../../tests/ffi/calloc.dart';
+
 // pthread_t pthread_self()
 typedef PthreadSelfFT = int Function();
 typedef PthreadSelfNFT = IntPtr Function();
@@ -34,11 +36,11 @@ class SchedParam extends Struct {
 
 main(args) {
   if (Platform.isMacOS) {
-    final policy = allocate<Int32>(count: 1);
-    final param = allocate<SchedParam>(count: 1);
+    final policy = calloc<Int32>(1);
+    final param = calloc<SchedParam>(1);
     Expect.equals(0, pthreadGetSchedParam(pthreadSelf(), policy, param));
     Expect.equals(15, param.ref.schedPriority);
-    free(policy);
-    free(param);
+    calloc.free(policy);
+    calloc.free(param);
   }
 }
diff --git a/runtime/tests/vm/dart_2/isolates/dart_api_create_lightweight_isolate_test.dart b/runtime/tests/vm/dart_2/isolates/dart_api_create_lightweight_isolate_test.dart
index 0daead0f8fbe..d35474e27f2b 100644
--- a/runtime/tests/vm/dart_2/isolates/dart_api_create_lightweight_isolate_test.dart
+++ b/runtime/tests/vm/dart_2/isolates/dart_api_create_lightweight_isolate_test.dart
@@ -14,6 +14,7 @@ import 'dart:isolate';
 import 'package:expect/expect.dart';
 import 'package:ffi/ffi.dart';
 
+import '../../../../../tests/ffi/calloc.dart';
 import '../../../../../tests/ffi/dylib_utils.dart';
 
 final bool isAOT = Platform.executable.contains('dart_precompiled_runtime');
@@ -62,7 +63,7 @@ abstract class FfiBindings {
       Expect.isTrue(isolate.address != 0);
       return isolate;
     } finally {
-      free(cname);
+      calloc.free(cname);
     }
   }
 
@@ -86,8 +87,8 @@ abstract class FfiBindings {
         onError != null ? onError.nativePort : 0,
         onExit != null ? onExit.nativePort : 0);
 
-    free(libraryUri);
-    free(functionName);
+    calloc.free(libraryUri);
+    calloc.free(functionName);
   }
 }
 
@@ -120,7 +121,7 @@ Future withPeerPointer(fun(Pointer<Void> peer)) async {
     // wait a little here to ensure the write of the callback has arrived.
     await Future.delayed(const Duration(milliseconds: 100));
     Expect.equals('xbz', Utf8.fromUtf8(peer.cast()));
-    free(peer);
+    calloc.free(peer);
   }
 }
 
diff --git a/runtime/tests/vm/dart_2/regress_41971_test.dart b/runtime/tests/vm/dart_2/regress_41971_test.dart
index 28f63ad1d5e9..7979d0d1e592 100644
--- a/runtime/tests/vm/dart_2/regress_41971_test.dart
+++ b/runtime/tests/vm/dart_2/regress_41971_test.dart
@@ -11,6 +11,8 @@ import 'dart:ffi';
 import 'package:expect/expect.dart';
 import 'package:ffi/ffi.dart';
 
+import '../../../../tests/ffi/calloc.dart';
+
 class X {
   int field;
   X(this.field);
@@ -35,8 +37,8 @@ int loadFrom(Pointer<Int32> p) {
 }
 
 void main() {
-  final p = allocate<Int32>(count: 128);
+  final p = calloc<Int32>(128);
   p[0] = 42;
   Expect.equals(42, loadFrom(p));
-  free(p);
+  calloc.free(p);
 }
diff --git a/runtime/tests/vm/dart_2/thread_priority_macos_test.dart b/runtime/tests/vm/dart_2/thread_priority_macos_test.dart
index b466eb0f26fa..fdce726a3629 100644
--- a/runtime/tests/vm/dart_2/thread_priority_macos_test.dart
+++ b/runtime/tests/vm/dart_2/thread_priority_macos_test.dart
@@ -10,6 +10,8 @@ import 'dart:io';
 import 'package:expect/expect.dart';
 import 'package:ffi/ffi.dart';
 
+import '../../../../tests/ffi/calloc.dart';
+
 // pthread_t pthread_self()
 typedef PthreadSelfFT = int Function();
 typedef PthreadSelfNFT = IntPtr Function();
@@ -34,11 +36,11 @@ class SchedParam extends Struct {
 
 main(args) {
   if (Platform.isMacOS) {
-    final policy = allocate<Int32>(count: 1);
-    final param = allocate<SchedParam>(count: 1);
+    final policy = calloc<Int32>(1);
+    final param = calloc<SchedParam>(1);
     Expect.equals(0, pthreadGetSchedParam(pthreadSelf(), policy, param));
     Expect.equals(15, param.ref.schedPriority);
-    free(policy);
-    free(param);
+    calloc.free(policy);
+    calloc.free(param);
   }
 }