reallocarray() is walled behind stupid feature macros on various
platforms and doesn't quite gain us much in that particular use case.
Signed-off-by: David Lamparter <equinox@diac24.net>
[u]int64_t is the only type in the intX_t family that needs
special-casing for printf since the calling convention may differ
between 32-bit and 64-bit systems.
Adding the L specifier allows us to eschew the gnarly-looking PRIu64.
Signed-off-by: David Lamparter <equinox@diac24.net>