Files
wxWidgets/include/wx/osx/private/available.h
Vadim Zeitlin fe311b9cc5 Use __builtin_available() when available in wxMac builds
The advantage of using this compiler builtin instead of our own platform
checks is that the compiler will warn us (if -Wunguarded-availability is
turned on for APIs introduced before 10.13 or by default for later ones)
if a check is forgotten, which is not the case for the manual checks.

Update the code to use WX_IS_MACOS_AVAILABLE() macro, which expands to
__builtin_available() when supported, and also use API_AVAILABLE() where
it makes sense to avoid having too many checks.
2019-04-18 00:02:34 +02:00

35 lines
1.5 KiB
C

///////////////////////////////////////////////////////////////////////////////
// Name: wx/osx/private/available.h
// Purpose: Helper for checking API availability under macOS.
// Author: Vadim Zeitlin
// Created: 2019-04-17
// Copyright: (c) 2019 Vadim Zeitlin <vadim@wxwidgets.org>
// Licence: wxWindows licence
///////////////////////////////////////////////////////////////////////////////
#ifndef _WX_OSX_PRIVATE_AVAILABLE_H_
#define _WX_OSX_PRIVATE_AVAILABLE_H_
// Xcode 9 adds new @available keyword and the corresponding __builtin_available
// builtin which should be used instead of manually checks for API availability
// as using this builtin suppresses the compiler -Wunguarded-availability
// warnings, so use it if possible for the implementation of our own macro.
#if defined(__clang__) && __has_builtin(__builtin_available)
#define WX_IS_MACOS_AVAILABLE(major, minor) \
__builtin_available(macOS major ## . ## minor, *)
// Note that we can't easily forward to API_AVAILABLE macro here, so go
// directly to its expansion instead.
#define WX_API_AVAILABLE_MACOS(major, minor) \
__attribute__((availability(macos,introduced=major ## . ## minor)))
#else // Not clang or old clang version without __builtin_available
#include "wx/platinfo.h"
#define WX_IS_MACOS_AVAILABLE(major, minor) \
wxPlatformInfo::Get().CheckOSVersion(major, minor)
#define WX_API_AVAILABLE_MACOS(major, minor)
#endif
#endif // _WX_OSX_PRIVATE_AVAILABLE_H_