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>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/corelib/global/qglobal.cpp b/src/corelib/global/qglobal.cpp
index 4ab5bd2edb..b662233d4e 100644
--- a/src/corelib/global/qglobal.cpp
+++ b/src/corelib/global/qglobal.cpp
@@ -92,7 +92,7 @@
 #  include <sys/systeminfo.h>
 #endif
 
-#if defined(Q_OS_DARWIN) && QT_HAS_INCLUDE(<IOKit/IOKitLib.h>)
+#if defined(Q_OS_DARWIN) && __has_include(<IOKit/IOKitLib.h>)
 #  include <IOKit/IOKitLib.h>
 #  include <private/qcore_mac_p.h>
 #endif
@@ -3041,7 +3041,7 @@ enum {
 */
 QByteArray QSysInfo::machineUniqueId()
 {
-#if defined(Q_OS_DARWIN) && QT_HAS_INCLUDE(<IOKit/IOKitLib.h>)
+#if defined(Q_OS_DARWIN) && __has_include(<IOKit/IOKitLib.h>)
     char uuid[UuidStringLen + 1];
     io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("IOPlatformExpertDevice"));
     QCFString stringRef = (CFStringRef)IORegistryEntryCreateCFProperty(service, CFSTR(kIOPlatformUUIDKey), kCFAllocatorDefault, 0);