diff options
| author | Tor Arne Vestbø <tor.arne.vestbo@qt.io> | 2019-12-08 23:47:10 +0100 |
|---|---|---|
| committer | Tor Arne Vestbø <tor.arne.vestbo@qt.io> | 2019-12-10 00:48:07 +0100 |
| commit | c3bd5ffdc8a3b459f18ba6e35fca93e29f3b0ab0 (patch) | |
| tree | 24d4c1350b6a08d35396377e83301bda3b4addb4 /src/corelib/kernel/qvariant.h | |
| parent | 191ac31598ccc9d7c8a2c83730755714f903b7ca (diff) | |
Don't wrap feature detection macros with QT_HAS_FOO() variants
Using wrappers for these macros is problematic when for example passing the
-frewrite-includes flag to preprocess sources before shipping off to distcc
or Icecream. It will also start producing warnings when compilers implement
http://eel.is/c++draft/cpp.cond#7.sentence-2. See for example
https://reviews.llvm.org/D49091
Both https://clang.llvm.org/docs/LanguageExtensions.html and the SD-6 document at
https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations
recommend defining '__has_foo(x) 0' as a fallback for compilers without the
macros, so that's what we go for.
Change-Id: I0298cd3b4a6ff6618821e34642a5ddd6728be767
Reviewed-by: Alex Richardson <arichardson.kde@gmail.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Diffstat (limited to 'src/corelib/kernel/qvariant.h')
| -rw-r--r-- | src/corelib/kernel/qvariant.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/src/corelib/kernel/qvariant.h b/src/corelib/kernel/qvariant.h index e7d3d9c835..a4957472ec 100644 --- a/src/corelib/kernel/qvariant.h +++ b/src/corelib/kernel/qvariant.h @@ -53,7 +53,7 @@ #include <QtCore/qbytearraylist.h> #endif -#if QT_HAS_INCLUDE(<variant>) && __cplusplus >= 201703L +#if __has_include(<variant>) && __cplusplus >= 201703L #include <variant> #elif defined(Q_CLANG_QDOC) namespace std { template<typename...> struct variant; } @@ -370,7 +370,7 @@ class Q_CORE_EXPORT QVariant static inline QVariant fromValue(const T &value) { return QVariant(qMetaTypeId<T>(), &value, QTypeInfo<T>::isPointer); } -#if (QT_HAS_INCLUDE(<variant>) && __cplusplus >= 201703L) || defined(Q_CLANG_QDOC) +#if (__has_include(<variant>) && __cplusplus >= 201703L) || defined(Q_CLANG_QDOC) template<typename... Types> static inline QVariant fromStdVariant(const std::variant<Types...> &value) { @@ -544,7 +544,7 @@ inline QVariant QVariant::fromValue(const QVariant &value) return value; } -#if QT_HAS_INCLUDE(<variant>) && __cplusplus >= 201703L +#if __has_include(<variant>) && __cplusplus >= 201703L template<> inline QVariant QVariant::fromValue(const std::monostate &) { |