diff options
-rw-r--r-- | src/corelib/thread/qrunnable.h | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/src/corelib/thread/qrunnable.h b/src/corelib/thread/qrunnable.h index 80945351ee..756156e583 100644 --- a/src/corelib/thread/qrunnable.h +++ b/src/corelib/thread/qrunnable.h @@ -101,27 +101,35 @@ public: namespace QtPrivate { template <typename T> -using is_function_pointer = std::conjunction<std::is_pointer<T>, std::is_function<std::remove_pointer_t<T>>>; +constexpr inline bool is_function_pointer_v = std::conjunction_v< + std::is_pointer<T>, + std::is_function<std::remove_pointer_t<T>> + >; template <typename T> -struct is_std_function : std::false_type {}; +constexpr inline bool is_std_function_v = false; template <typename T> -struct is_std_function<std::function<T>> : std::true_type {}; +constexpr inline bool is_std_function_v<std::function<T>> = true; } // namespace QtPrivate template <typename Callable, QRunnable::if_callable<Callable>> QRunnable *QRunnable::create(Callable &&functionToRun) { - bool is_null = false; - if constexpr(QtPrivate::is_std_function<std::decay_t<Callable>>::value) - is_null = !functionToRun; - - if constexpr(QtPrivate::is_function_pointer<std::decay_t<Callable>>::value) { - const void *functionPtr = reinterpret_cast<void *>(functionToRun); - is_null = !functionPtr; + using F = std::decay_t<Callable>; + constexpr bool is_std_function = QtPrivate::is_std_function_v<F>; + constexpr bool is_function_pointer = QtPrivate::is_function_pointer_v<F>; + if constexpr (is_std_function || is_function_pointer) { + bool is_null; + if constexpr (is_std_function) { + is_null = !functionToRun; + } else if constexpr (is_function_pointer) { + // shut up warnings about functions always having a non-null address: + const void *functionPtr = reinterpret_cast<void *>(functionToRun); + is_null = !functionPtr; + } + if (is_null) + return warnNullCallable(); } - if (is_null) - return warnNullCallable(); return new QGenericRunnable(std::forward<Callable>(functionToRun)); } |