The decltype() of a const auto variable will be const T, for some
T. GCC warns that in the static_cast, said const is ignored.
Fix by not casting, but declaring a variable of fitting type. Add a
scope so the next reader doesn't have to go hunting for further uses
of 'readResult' or, now, 'expected'.
Change-Id: Iebc828a522810c6f2514fb3542d8c76c755ec7a5
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
6cc830f7a6