Hi,

While experimenting building qt from source with c++23, I got the error:

C:/Android/android-sdk/ndk/28.2.13676358/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/include/c++/v1/__memory/unique_ptr.h:66:19: error: invalid application of 'sizeof' to an incomplete type 'QSingleShotTimer'
   66 |     static_assert(sizeof(_Tp) >= 0, "cannot delete an incomplete type");
      |                   ^~~~~~~~~~~
C:/Android/android-sdk/ndk/28.2.13676358/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/include/c++/v1/__memory/unique_ptr.h:279:7: note: in instantiation of member function 'std::default_delete<QSingleShotTimer>::operator()' requested here
  279 |       _ptr.second()(__tmp);
      |       ^
C:/Android/android-sdk/ndk/28.2.13676358/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/include/c++/v1/__memory/unique_ptr.h:249:71: note: in instantiation of member function 'std::unique_ptr<QSingleShotTimer>::reset' requested here
  249 |   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 ~unique_ptr() { reset(); }
      |                                                                       ^
D:/a/qt/qt/qtbase/src/corelib/kernel/qsingleshottimer_p.h:54:11: note: in instantiation of member function 'std::unique_ptr<QSingleShotTimer>::~unique_ptr' requested here
   54 |     class StartTimerEvent : public QTimerEvent
      |           ^
D:/a/qt/qt/qtbase/src/corelib/kernel/qsingleshottimer_p.h:54:11: note: in implicit destructor for 'QSingleShotTimer::StartTimerEvent' first required here
D:/a/qt/qt/qtbase/src/corelib/kernel/qsingleshottimer_p.h:32:25: note: definition of 'QSingleShotTimer' is not complete until the closing '}'
   32 | class Q_AUTOTEST_EXPORT QSingleShotTimer : public QObject
      |                         ^