Various FreeBSD source and header files need a typedef __size_t via
<sys/_types.h>. Unfortunately the GCC provided <stddef.h> uses
#if (defined (__FreeBSD__) && (__FreeBSD__ >= 5)) \
|| defined(__DragonFly__) \
|| defined(__FreeBSD_kernel__)
/* __size_t is a typedef on FreeBSD 5, must not trash it. */
#elif defined (__VMS__)
/* __size_t is also a typedef on VMS. */
#else
#define __size_t
#endif
and therefore defines __size_t on Newlib targets which would trash a
__size_t typedef. Include <stddef.h> before <sys/_types.h> in
<sys/types.h> and undefine __size_t in <sys/_types.h> as a workaround.
Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>