compiler warning: discard result explicitly

Signal/src/ViewControllers/ConversationView/Cells/ConversationMediaView.swift

@@ -128,7 +128,7 @@ public class ConversationMediaView: UIView {
         animatedImageView.backgroundColor = Theme.offBackgroundColor
         addSubview(animatedImageView)
         animatedImageView.autoPinEdgesToSuperviewEdges()
-        addUploadProgressIfNecessary(animatedImageView)
+        _ = addUploadProgressIfNecessary(animatedImageView)
 
         loadBlock = { [weak self] in
             guard let strongSelf = self else {
@@ -177,7 +177,7 @@ public class ConversationMediaView: UIView {
         stillImageView.backgroundColor = Theme.offBackgroundColor
         addSubview(stillImageView)
         stillImageView.autoPinEdgesToSuperviewEdges()
-        addUploadProgressIfNecessary(stillImageView)
+        _ = addUploadProgressIfNecessary(stillImageView)
         loadBlock = { [weak self] in
             guard let strongSelf = self else {
                 return

Signal/src/call/Speakerbox/CallKitCallUIAdaptee.swift

@@ -113,7 +113,7 @@ final class CallKitCallUIAdaptee: NSObject, CallUIAdaptee, CXProviderDelegate {
         let call = SignalCall.outgoingCall(localId: UUID(), remotePhoneNumber: handle)
 
         // make sure we don't terminate audio session during call
-        self.audioSession.startAudioActivity(call.audioActivity)
+        _ = self.audioSession.startAudioActivity(call.audioActivity)
 
         // Add the new outgoing call to the app's list of calls.
         // So we can find it in the provider delegate callbacks.
@@ -385,7 +385,7 @@ final class CallKitCallUIAdaptee: NSObject, CallUIAdaptee, CXProviderDelegate {
 
         Logger.debug("Received")
 
-        self.audioSession.startAudioActivity(self.audioActivity)
+        _ = self.audioSession.startAudioActivity(self.audioActivity)
         self.audioSession.isRTCAudioEnabled = true
     }
 

Signal/src/call/UserInterface/CallUIAdapter.swift

@@ -141,7 +141,7 @@ extension CallUIAdaptee {
         AssertIsOnMainThread()
 
         // make sure we don't terminate audio session during call
-        audioSession.startAudioActivity(call.audioActivity)
+        _ = audioSession.startAudioActivity(call.audioActivity)
 
         let callerName = self.contactsManager.displayName(forPhoneIdentifier: call.remotePhoneNumber)
         adaptee.reportIncomingCall(call, callerName: callerName)