From 2a8b6f05c8b4f6e1aacbfaa57d301e59739d199d Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Sat, 27 Jul 2019 17:01:25 +0200
Subject: [PATCH] Fix build for GCC.

---
 Telegram/SourceFiles/mtproto/rpc_sender.h | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/Telegram/SourceFiles/mtproto/rpc_sender.h b/Telegram/SourceFiles/mtproto/rpc_sender.h
index b0c83d59a..068bd4d32 100644
--- a/Telegram/SourceFiles/mtproto/rpc_sender.h
+++ b/Telegram/SourceFiles/mtproto/rpc_sender.h
@@ -343,15 +343,17 @@ protected:
 
 };
 
-template <typename TReturn, typename TReceiver>
+template <typename TReceiver>
 class RPCDoneHandlerBareOwned : public RPCOwnedDoneHandler { // done(from, end)
-	using CallbackType = TReturn (TReceiver::*)(const mtpPrime *, const mtpPrime *);
+	using CallbackType = bool (TReceiver::*)(const mtpPrime *, const mtpPrime *);
 
 public:
     RPCDoneHandlerBareOwned(TReceiver *receiver, CallbackType onDone) : RPCOwnedDoneHandler(receiver), _onDone(onDone) {
 	}
 	bool operator()(mtpRequestId requestId, const mtpPrime *from, const mtpPrime *end) override {
-		if (_owner) (static_cast<TReceiver*>(_owner)->*_onDone)(from, end);
+		return _owner
+			? (static_cast<TReceiver*>(_owner)->*_onDone)(from, end)
+			: true;
 	}
 
 private:
@@ -713,9 +715,9 @@ private:
 
 class RPCSender {
 public:
-	template <typename TReturn, typename TReceiver> // done(from, end)
-	RPCDoneHandlerPtr rpcDone(TReturn (TReceiver::*onDone)(const mtpPrime *, const mtpPrime *)) {
-		return RPCDoneHandlerPtr(new RPCDoneHandlerBareOwned<TReturn, TReceiver>(static_cast<TReceiver*>(this), onDone));
+	template <typename TReceiver> // done(from, end)
+	RPCDoneHandlerPtr rpcDone(bool (TReceiver::*onDone)(const mtpPrime *, const mtpPrime *)) {
+		return RPCDoneHandlerPtr(new RPCDoneHandlerBareOwned<TReceiver>(static_cast<TReceiver*>(this), onDone));
 	}
 
 	template <typename TReceiver> // done(from, end, req_id)