In my case it looks in vcruntime.h which includes:
#ifdef _WIN64
typedef unsigned __int64 size_t;
typedef __int64 ptrdiff_t;
typedef __int64 intptr_t;
#else
typedef unsigned int size_t;
typedef int ptrdiff_t;
typedef int intptr_t;
#endif
and it gives me a qualified type (in x64 win case) LongLong which is wrong it should be IntPtr / nint?
Similarly for size_t it should be nuint and for long/ulong to use CLong / CULong.