diff --git a/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m b/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m
index 696069c200f503c8be40b49e193d488b5c56fec6..ea2b01ee1d77fe182808dd35e17cd6a5cb39755d 100644
--- a/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m
+++ b/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m
@@ -43,7 +43,7 @@
 
 - (instancetype)init {
   if ((self = [super init])) {
-    _unmanagedQueue = grpc_completion_queue_create();
+    _unmanagedQueue = grpc_completion_queue_create(NULL);
 
     // This is for the following block to capture the pointer by value (instead
     // of retaining self and doing self->_unmanagedQueue). This is essential
@@ -64,7 +64,8 @@
       while (YES) {
         // The following call blocks until an event is available.
         grpc_event event = grpc_completion_queue_next(unmanagedQueue,
-                                                      gpr_inf_future(GPR_CLOCK_REALTIME));
+                                                      gpr_inf_future(GPR_CLOCK_REALTIME),
+                                                      NULL);
         GRPCQueueCompletionHandler handler;
         switch (event.type) {
           case GRPC_OP_COMPLETE:
diff --git a/src/objective-c/GRPCClient/private/GRPCHost.m b/src/objective-c/GRPCClient/private/GRPCHost.m
index d902f95b516b31b0c859eabe2bac9f8d52d28039..a7142d0f009e1007ff5cbc4b18ddf222bf9b2408 100644
--- a/src/objective-c/GRPCClient/private/GRPCHost.m
+++ b/src/objective-c/GRPCClient/private/GRPCHost.m
@@ -97,7 +97,7 @@
                                   queue.unmanagedQueue,
                                   path.UTF8String,
                                   self.hostName.UTF8String,
-                                  gpr_inf_future(GPR_CLOCK_REALTIME));
+                                  gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
 }
 
 - (GRPCChannel *)channel {
diff --git a/src/objective-c/GRPCClient/private/GRPCUnsecuredChannel.m b/src/objective-c/GRPCClient/private/GRPCUnsecuredChannel.m
index 070a529629a6ef6e5d3e3f0685f6b94288798e46..15b6ffc75cf06e9010e2c0b6c45dd3a0f706ba76 100644
--- a/src/objective-c/GRPCClient/private/GRPCUnsecuredChannel.m
+++ b/src/objective-c/GRPCClient/private/GRPCUnsecuredChannel.m
@@ -38,7 +38,7 @@
 @implementation GRPCUnsecuredChannel
 
 - (instancetype)initWithHost:(NSString *)host {
-  return (self = [super initWithChannel:grpc_insecure_channel_create(host.UTF8String, NULL)]);
+  return (self = [super initWithChannel:grpc_insecure_channel_create(host.UTF8String, NULL, NULL)]);
 }
 
 // TODO(jcanizales): GRPCSecureChannel and GRPCUnsecuredChannel are just convenience initializers
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
index 951c0510369fda65442fa12b39fabb783178eb52..fe3d51da53a58a409621433744fdd028872e64a3 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
@@ -282,7 +282,7 @@
     for (GRPCOperation *operation in operations) {
       [operation finish];
     }
-  }));
+  }), NULL);
   gpr_free(ops_array);
 
   if (error != GRPC_CALL_OK) {
@@ -293,7 +293,7 @@
 }
 
 - (void)cancel {
-  grpc_call_cancel(_call);
+  grpc_call_cancel(_call, NULL);
 }
 
 - (void)dealloc {