when I include header: <QtCore> or <QtGui> that include qendian.h, and build will error

when I include QtCore or QtGui header that include qendian.h, and build my project that will get errors:
/opt/Qt/5.12.0/gcc_64/include/QtCore/qendian.h:165:61: error: redeclaration 'constexpr T qbswap(T) [with T = qfloat16]' differs in 'constexpr'
template <> inline qfloat16 qbswap<qfloat16>(qfloat16 source)
^
/opt/Qt/5.12.0/gcc_64/include/QtCore/qendian.h:96:42: error: from previous declaration 'constexpr T qbswap(T) [with T = qfloat16]'
template <typename T> Q_DECL_CONSTEXPR T qbswap(T source);
^
/opt/Qt/5.12.0/gcc_64/include/QtCore/qendian.h:170:52: error: redeclaration 'constexpr T qbswap(T) [with T = float]' differs in 'constexpr'
template <> inline float qbswap<float>(float source)
^
/opt/Qt/5.12.0/gcc_64/include/QtCore/qendian.h:96:42: error: from previous declaration 'constexpr T qbswap(T) [with T = float]'
template <typename T> Q_DECL_CONSTEXPR T qbswap(T source);
^
/opt/Qt/5.12.0/gcc_64/include/QtCore/qendian.h:175:55: error: redeclaration 'constexpr T qbswap(T) [with T = double]' differs in 'constexpr'
template <> inline double qbswap<double>(double source)
^
/opt/Qt/5.12.0/gcc_64/include/QtCore/qendian.h:96:42: error: from previous declaration 'constexpr T qbswap(T) [with T = double]'
template <typename T> Q_DECL_CONSTEXPR T qbswap(T source);