Be more cautious with rvalues

Clang on FreeBSD doesn't seem to be playing nice in Release
configuration. See the comment in the committed code.

1 files changed, 8 insertions, 2 deletions

diff --git a/lib/connection.cpp b/lib/connection.cpp
index 2bdbb2e5..a2b1b94e 100644
--- a/lib/connection.cpp
+++ b/lib/connection.cpp
@@ -281,7 +281,8 @@ void Connection::sync(int timeout)
 
 void Connection::onSyncSuccess(SyncData &&data) {
     d->data->setLastEvent(data.nextBatch());
-    for (auto&& roomData: data.takeRoomData())
+    auto allRoomData = data.takeRoomData();
+    for (auto&& roomData: allRoomData)
     {
         const auto forgetIdx = d->roomIdsToForget.indexOf(roomData.roomId);
         if (forgetIdx != -1)
@@ -302,7 +303,12 @@ void Connection::onSyncSuccess(SyncData &&data) {
             r->updateData(std::move(roomData));
         QCoreApplication::processEvents();
     }
-    for (auto&& accountEvent: data.takeAccountData())
+    // `for (auto&& accountEvent: data.takeAccountData())` doesn't work well
+    // with Clang on FreeBSD in Release configuration; it seems that
+    // the lifetime of the returned rvalue does not extend (violating the
+    // standard) and accountEvent refers to garbage in the loop body as a result.
+    auto allAccountData = data.takeAccountData();
+    for (auto&& accountEvent: allAccountData)
     {
         if (accountEvent->type() == EventType::DirectChat)
         {