diff --git a/src/objective-c/ProtoRPC/ProtoMethod.m b/src/objective-c/ProtoRPC/ProtoMethod.m
index 4bef10af0e2..ed585acfb96 100644
--- a/src/objective-c/ProtoRPC/ProtoMethod.m
+++ b/src/objective-c/ProtoRPC/ProtoMethod.m
@@ -18,7 +18,10 @@
 
 #import "ProtoMethod.h"
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-implementations"
 @implementation ProtoMethod
+#pragma clang diagnostic pop
 - (instancetype)initWithPackage:(NSString *)package
                         service:(NSString *)service
                          method:(NSString *)method {
diff --git a/src/objective-c/ProtoRPC/ProtoRPC.m b/src/objective-c/ProtoRPC/ProtoRPC.m
index 1ecfcc5b0ef..20b9d04cd84 100644
--- a/src/objective-c/ProtoRPC/ProtoRPC.m
+++ b/src/objective-c/ProtoRPC/ProtoRPC.m
@@ -42,7 +42,10 @@ static NSError *ErrorForBadProto(id proto, Class expectedClass, NSError *parsing
                          userInfo:info];
 }
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-implementations"
 @implementation ProtoRPC {
+#pragma clang diagnostic pop
   id<GRXWriteable> _responseWriteable;
 }
 
diff --git a/src/objective-c/ProtoRPC/ProtoService.m b/src/objective-c/ProtoRPC/ProtoService.m
index be6089f0a46..611cee46bfc 100644
--- a/src/objective-c/ProtoRPC/ProtoService.m
+++ b/src/objective-c/ProtoRPC/ProtoService.m
@@ -24,7 +24,10 @@
 #import "ProtoMethod.h"
 #import "ProtoRPC.h"
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-implementations"
 @implementation ProtoService {
+#pragma clang diagnostic pop
   NSString *_host;
   NSString *_packageName;
   NSString *_serviceName;
diff --git a/src/objective-c/RxLibrary/GRXConcurrentWriteable.m b/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
index 37bc975f874..c2623134960 100644
--- a/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
+++ b/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
@@ -64,21 +64,25 @@
 }
 
 - (void)enqueueSuccessfulCompletion {
+  __weak typeof(self) weakSelf = self;
   dispatch_async(_writeableQueue, ^{
-    BOOL finished = NO;
-    @synchronized (self) {
-      if (!_alreadyFinished) {
-        _alreadyFinished = YES;
-      } else {
-        finished = YES;
+    typeof(self) strongSelf = weakSelf;
+    if (strongSelf) {
+      BOOL finished = NO;
+      @synchronized (self) {
+        if (!strongSelf->_alreadyFinished) {
+          strongSelf->_alreadyFinished = YES;
+        } else {
+          finished = YES;
+        }
+      }
+      if (!finished) {
+        // Cancellation is now impossible. None of the other three blocks can run concurrently with
+        // this one.
+        [self.writeable writesFinishedWithError:nil];
+        // Skip any possible message to the wrapped writeable enqueued after this one.
+        self.writeable = nil;
       }
-    }
-    if (!finished) {
-      // Cancellation is now impossible. None of the other three blocks can run concurrently with
-      // this one.
-      [self.writeable writesFinishedWithError:nil];
-      // Skip any possible message to the wrapped writeable enqueued after this one.
-      self.writeable = nil;
     }
   });
 }