Bug#42733: Type-punning warnings when compiling MySQL -- strict aliasing violations.

Silence bogus aliasing warning through a pointer indirection. Also,
no need to check the return of a placement new.

sql/rpl_handler.cc

@@ -99,22 +99,34 @@ int delegates_init()
                             MY_ALIGNOF(long)> relay_io_mem;
 #endif
 
-  if (!(transaction_delegate= new (trans_mem.data) Trans_delegate)
-      || (!transaction_delegate->is_inited())
-      || !(binlog_storage_delegate=
-           new (storage_mem.data) Binlog_storage_delegate)
-      || (!binlog_storage_delegate->is_inited())
+  void *place_trans_mem= trans_mem.data;
+  void *place_storage_mem= storage_mem.data;
+
+  transaction_delegate= new (place_trans_mem) Trans_delegate;
+
+  if (!transaction_delegate->is_inited())
+    return 1;
+
+  binlog_storage_delegate= new (place_storage_mem) Binlog_storage_delegate;
+
+  if (!binlog_storage_delegate->is_inited())
+    return 1;
+
 #ifdef HAVE_REPLICATION
-      || !(binlog_transmit_delegate=
-           new (transmit_mem.data) Binlog_transmit_delegate)
-      || (!binlog_transmit_delegate->is_inited())
-      || !(binlog_relay_io_delegate=
-           new (relay_io_mem.data) Binlog_relay_IO_delegate)
-      || (!binlog_relay_io_delegate->is_inited())
-#endif /* HAVE_REPLICATION */
-      )
+  void *place_transmit_mem= transmit_mem.data;
+  void *place_relay_io_mem= relay_io_mem.data;
+
+  binlog_transmit_delegate= new (place_transmit_mem) Binlog_transmit_delegate;
+
+  if (!binlog_transmit_delegate->is_inited())
     return 1;
 
+  binlog_relay_io_delegate= new (place_relay_io_mem) Binlog_relay_IO_delegate;
+
+  if (!binlog_relay_io_delegate->is_inited())
+    return 1;
+#endif
+
   if (pthread_key_create(&RPL_TRANS_BINLOG_INFO, NULL))
     return 1;
   return 0;